Infectious Diseases

Children who were severely ill with multisystem inflammatory syndrome in children (MIS-C) related to COVID-19 infection appear to show excellent cardiovascular and noncardiovascular outcomes by 6 months, according to data published in JAMA Pediatrics.

MIS-C is a life-threatening complication of COVID-19 infection and data on outcomes are limited, wrote the authors, led by Dongngan T. Truong, MD, MSSI, with Children’s Healthcare of Atlanta Cardiology, Emory University School of Medicine in Atlanta, Georgia. These 6-month results are from the Long-Term Outcomes After the Multisystem Inflammatory Syndrome in Children (MUSIC) study, sponsored by the National Heart, Lung, and Blood Institute.

Researchers found in this cohort study of 1204 participants that by 6 months after hospital discharge, 99% had normalization of left ventricular systolic function, and 92.3% had normalized coronary artery dimensions. More than 95% reported being more than 90% back to baseline health.

Patient-Reported Outcomes Measurement Information Systems (PROMIS) Global Health scores were at least equivalent to prepandemic population normative values. PROMIS Global Health parent/guardian proxy median T scores for fatigue, global health, and pain interference improved significantly from 2 weeks to 6 months: fatigue, 56.1 vs 48.9; global health, 48.8 vs 51.3; pain interference, 53.0 vs 43.3 (P < .001).

The most common symptoms reported at 2 weeks were fatigue (15.9%) and low stamina/energy (9.2%); both decreased to 3.4% and 3.3%, respectively, by 6 months. The most common cardiovascular symptom at 2 weeks was palpitations (1.5%), which decreased to 0.6%.

 

Chest Pain Increased Over Time

Reports of chest pain, however, reportedly increased over time, with 1.3% reporting chest pain at rest at 2 weeks and 2.2% at 6 months. Although gastrointestinal symptoms were common during the acute MIS-C, only 5.3% of respondents reported those symptoms at 2 weeks.

Children in the cohort had a median age of 9 years, and 60% were men. They self-identified with the following races and ethnicities: American Indian or Alaska Native (0.1%), Asian (3.3%), Black (27.0%), Hawaiian Native or Other Pacific Islander (0.2%), Hispanic or Latino (26.9%), multiracial (2.7%), White (31.2%), other (1.0%), and unknown or refused to specify (7.6%). Authors wrote that the cohort was followed-up to 2 years after illness onset and long-term results are not yet known.

 

Time to Exhale

David J. Goldberg, MD, with the Cardiac Center, Children’s Hospital of Philadelphia, Pennsylvania, and colleagues, wrote in an accompanying editorial that “the decreased frequency of the disease along (with) the reassuring reports on midterm outcomes can allow the pediatric community a moment of collective exhale.”

The editorialists note that of those who initially presented with myocardial dysfunction, all but one patient evaluated had a normal ejection fraction at follow-up. Energy, sleep, appetite, cognition, and mood also normalized by midterm.

“The results of the MUSIC study add to the emerging midterm outcomes data suggesting a near-complete cardiovascular recovery in the overwhelming majority of patients who develop MIS-C,” Goldberg and colleagues wrote. “Despite initial concerns, driven by the severity of acute presentation at diagnosis and longer-term questions that remain (for example, does coronary microvascular dysfunction persist even after normalization of coronary artery z score?), these data suggest an encouraging outlook for the long-term health of affected children.”

The Centers for Disease Control and Prevention and other agencies have reported a declining overall incidence of MIS-C and highlighted the protective value of vaccination. 

The editorialists add, however, that while the drop in MIS-C cases is encouraging, cases are still reported, especially amid high viral activity periods, “and nearly half of affected children continue to require intensive care in the acute phase of illness.”

Truong reported grants from the National Institutes of Health and serving as coprincipal investigator for Pfizer for research on COVID-19 vaccine-associated myocarditis funded by Pfizer and occurring through the framework of the National Heart, Lung, and Blood Institute’s Pediatric Heart Network outside the submitted work. One coauthor reported grants from Pfizer and Boston Scientific outside the submitted work. One coauthor reported receiving grants from Additional Ventures Foundation outside the submitted work. One coauthor reported receiving consultant fees from Amryt Pharma, Chiesi, Esperion, and Ultragenyx outside the submitted work. A coauthor reported receiving consultant fees from Larimar Therapeutics for mitochondrial therapies outside the submitted work. One coauthor reported being an employee of Takeda Pharmaceuticals since July 2023. One editorialist reported grants from Childhood Arthritis and Rheumatology Research Alliance and the Arthritis Foundation, Academy Health, and the Gordon and Betty Moore Foundation during the conduct of the study.

A version of this article first appeared on Medscape.com.

Children who were severely ill with multisystem inflammatory syndrome in children (MIS-C) related to COVID-19 infection appear to show excellent cardiovascular and noncardiovascular outcomes by 6 months, according to data published in JAMA Pediatrics.

MIS-C is a life-threatening complication of COVID-19 infection and data on outcomes are limited, wrote the authors, led by Dongngan T. Truong, MD, MSSI, with Children’s Healthcare of Atlanta Cardiology, Emory University School of Medicine in Atlanta, Georgia. These 6-month results are from the Long-Term Outcomes After the Multisystem Inflammatory Syndrome in Children (MUSIC) study, sponsored by the National Heart, Lung, and Blood Institute.

Researchers found in this cohort study of 1204 participants that by 6 months after hospital discharge, 99% had normalization of left ventricular systolic function, and 92.3% had normalized coronary artery dimensions. More than 95% reported being more than 90% back to baseline health.

Patient-Reported Outcomes Measurement Information Systems (PROMIS) Global Health scores were at least equivalent to prepandemic population normative values. PROMIS Global Health parent/guardian proxy median T scores for fatigue, global health, and pain interference improved significantly from 2 weeks to 6 months: fatigue, 56.1 vs 48.9; global health, 48.8 vs 51.3; pain interference, 53.0 vs 43.3 (P < .001).

The most common symptoms reported at 2 weeks were fatigue (15.9%) and low stamina/energy (9.2%); both decreased to 3.4% and 3.3%, respectively, by 6 months. The most common cardiovascular symptom at 2 weeks was palpitations (1.5%), which decreased to 0.6%.

 

Chest Pain Increased Over Time

Reports of chest pain, however, reportedly increased over time, with 1.3% reporting chest pain at rest at 2 weeks and 2.2% at 6 months. Although gastrointestinal symptoms were common during the acute MIS-C, only 5.3% of respondents reported those symptoms at 2 weeks.

Children in the cohort had a median age of 9 years, and 60% were men. They self-identified with the following races and ethnicities: American Indian or Alaska Native (0.1%), Asian (3.3%), Black (27.0%), Hawaiian Native or Other Pacific Islander (0.2%), Hispanic or Latino (26.9%), multiracial (2.7%), White (31.2%), other (1.0%), and unknown or refused to specify (7.6%). Authors wrote that the cohort was followed-up to 2 years after illness onset and long-term results are not yet known.

 

Time to Exhale

David J. Goldberg, MD, with the Cardiac Center, Children’s Hospital of Philadelphia, Pennsylvania, and colleagues, wrote in an accompanying editorial that “the decreased frequency of the disease along (with) the reassuring reports on midterm outcomes can allow the pediatric community a moment of collective exhale.”

The editorialists note that of those who initially presented with myocardial dysfunction, all but one patient evaluated had a normal ejection fraction at follow-up. Energy, sleep, appetite, cognition, and mood also normalized by midterm.

“The results of the MUSIC study add to the emerging midterm outcomes data suggesting a near-complete cardiovascular recovery in the overwhelming majority of patients who develop MIS-C,” Goldberg and colleagues wrote. “Despite initial concerns, driven by the severity of acute presentation at diagnosis and longer-term questions that remain (for example, does coronary microvascular dysfunction persist even after normalization of coronary artery z score?), these data suggest an encouraging outlook for the long-term health of affected children.”

The Centers for Disease Control and Prevention and other agencies have reported a declining overall incidence of MIS-C and highlighted the protective value of vaccination. 

The editorialists add, however, that while the drop in MIS-C cases is encouraging, cases are still reported, especially amid high viral activity periods, “and nearly half of affected children continue to require intensive care in the acute phase of illness.”

Truong reported grants from the National Institutes of Health and serving as coprincipal investigator for Pfizer for research on COVID-19 vaccine-associated myocarditis funded by Pfizer and occurring through the framework of the National Heart, Lung, and Blood Institute’s Pediatric Heart Network outside the submitted work. One coauthor reported grants from Pfizer and Boston Scientific outside the submitted work. One coauthor reported receiving grants from Additional Ventures Foundation outside the submitted work. One coauthor reported receiving consultant fees from Amryt Pharma, Chiesi, Esperion, and Ultragenyx outside the submitted work. A coauthor reported receiving consultant fees from Larimar Therapeutics for mitochondrial therapies outside the submitted work. One coauthor reported being an employee of Takeda Pharmaceuticals since July 2023. One editorialist reported grants from Childhood Arthritis and Rheumatology Research Alliance and the Arthritis Foundation, Academy Health, and the Gordon and Betty Moore Foundation during the conduct of the study.

A version of this article first appeared on Medscape.com.

Children who were severely ill with multisystem inflammatory syndrome in children (MIS-C) related to COVID-19 infection appear to show excellent cardiovascular and noncardiovascular outcomes by 6 months, according to data published in JAMA Pediatrics.

MIS-C is a life-threatening complication of COVID-19 infection and data on outcomes are limited, wrote the authors, led by Dongngan T. Truong, MD, MSSI, with Children’s Healthcare of Atlanta Cardiology, Emory University School of Medicine in Atlanta, Georgia. These 6-month results are from the Long-Term Outcomes After the Multisystem Inflammatory Syndrome in Children (MUSIC) study, sponsored by the National Heart, Lung, and Blood Institute.

Researchers found in this cohort study of 1204 participants that by 6 months after hospital discharge, 99% had normalization of left ventricular systolic function, and 92.3% had normalized coronary artery dimensions. More than 95% reported being more than 90% back to baseline health.

Patient-Reported Outcomes Measurement Information Systems (PROMIS) Global Health scores were at least equivalent to prepandemic population normative values. PROMIS Global Health parent/guardian proxy median T scores for fatigue, global health, and pain interference improved significantly from 2 weeks to 6 months: fatigue, 56.1 vs 48.9; global health, 48.8 vs 51.3; pain interference, 53.0 vs 43.3 (P < .001).

The most common symptoms reported at 2 weeks were fatigue (15.9%) and low stamina/energy (9.2%); both decreased to 3.4% and 3.3%, respectively, by 6 months. The most common cardiovascular symptom at 2 weeks was palpitations (1.5%), which decreased to 0.6%.

 

Chest Pain Increased Over Time

Reports of chest pain, however, reportedly increased over time, with 1.3% reporting chest pain at rest at 2 weeks and 2.2% at 6 months. Although gastrointestinal symptoms were common during the acute MIS-C, only 5.3% of respondents reported those symptoms at 2 weeks.

Children in the cohort had a median age of 9 years, and 60% were men. They self-identified with the following races and ethnicities: American Indian or Alaska Native (0.1%), Asian (3.3%), Black (27.0%), Hawaiian Native or Other Pacific Islander (0.2%), Hispanic or Latino (26.9%), multiracial (2.7%), White (31.2%), other (1.0%), and unknown or refused to specify (7.6%). Authors wrote that the cohort was followed-up to 2 years after illness onset and long-term results are not yet known.

 

Time to Exhale

David J. Goldberg, MD, with the Cardiac Center, Children’s Hospital of Philadelphia, Pennsylvania, and colleagues, wrote in an accompanying editorial that “the decreased frequency of the disease along (with) the reassuring reports on midterm outcomes can allow the pediatric community a moment of collective exhale.”

The editorialists note that of those who initially presented with myocardial dysfunction, all but one patient evaluated had a normal ejection fraction at follow-up. Energy, sleep, appetite, cognition, and mood also normalized by midterm.

“The results of the MUSIC study add to the emerging midterm outcomes data suggesting a near-complete cardiovascular recovery in the overwhelming majority of patients who develop MIS-C,” Goldberg and colleagues wrote. “Despite initial concerns, driven by the severity of acute presentation at diagnosis and longer-term questions that remain (for example, does coronary microvascular dysfunction persist even after normalization of coronary artery z score?), these data suggest an encouraging outlook for the long-term health of affected children.”

The Centers for Disease Control and Prevention and other agencies have reported a declining overall incidence of MIS-C and highlighted the protective value of vaccination. 

The editorialists add, however, that while the drop in MIS-C cases is encouraging, cases are still reported, especially amid high viral activity periods, “and nearly half of affected children continue to require intensive care in the acute phase of illness.”

Truong reported grants from the National Institutes of Health and serving as coprincipal investigator for Pfizer for research on COVID-19 vaccine-associated myocarditis funded by Pfizer and occurring through the framework of the National Heart, Lung, and Blood Institute’s Pediatric Heart Network outside the submitted work. One coauthor reported grants from Pfizer and Boston Scientific outside the submitted work. One coauthor reported receiving grants from Additional Ventures Foundation outside the submitted work. One coauthor reported receiving consultant fees from Amryt Pharma, Chiesi, Esperion, and Ultragenyx outside the submitted work. A coauthor reported receiving consultant fees from Larimar Therapeutics for mitochondrial therapies outside the submitted work. One coauthor reported being an employee of Takeda Pharmaceuticals since July 2023. One editorialist reported grants from Childhood Arthritis and Rheumatology Research Alliance and the Arthritis Foundation, Academy Health, and the Gordon and Betty Moore Foundation during the conduct of the study.

A version of this article first appeared on Medscape.com.

TOPLINE:

The use of valaciclovir as prophylaxis prevents herpes zoster (HZ) in patients with systemic lupus erythematosus (SLE) receiving anifrolumab treatment, with no cases of zoster reported during the follow-up period in patients receiving valaciclovir.

METHODOLOGY:

• Anifrolumab, a human monoclonal antibody binding to type I interferon receptor subunit 1, increases the risk for HZ in patients with SLE; however, specific recommendations to prevent HZ are currently nonexistent for patients with SLE receiving anifrolumab.
• Researchers conducted a multicenter observational study in France from November 2021 to July 2024 to evaluate the prophylactic benefits of valaciclovir in 132 patients with SLE (mean age, 42 years; 92% women) treated with anifrolumab for ≥ 3 months.
• Among these patients, 87 received either 500 mg/d valaciclovir (n = 69) or 1000 mg/d valaciclovir (n = 18) as prophylaxis, whereas 45 did not receive valaciclovir.
• The patients were followed up for a median duration of 234 days under anifrolumab treatment, with monitoring for the development of herpes zoster.

TAKEAWAY:

• The risk for HZ was significantly lower in patients who received valaciclovir than in those who did not (hazard ratio, 0.08; P = .01).
• None of the patients treated with valaciclovir developed HZ during the survey period.
• The frequency of HZ in patients who did not receive valaciclovir increased progressively from 2.2% at 3 months to 6.2% at 6 months, reaching 23% at 12 months.
• None of the reported cases of HZ required hospitalization or led to anifrolumab discontinuation, although one patient developed neuralgia.

IN PRACTICE:

“Prophylactic treatment with valaciclovir is effective for preventing HZ [herpes zoster] infection in SLE patients treated with anifrolumab,” the authors wrote. “This finding is particularly relevant for SLE patients who cannot receive the recombinant HZ vaccine or for whom it is unavailable,” they added.

SOURCE:

The study was led by Ludovic Trefond, MD, PhD, Centre Hospitalier Universitaire de Clermont-Ferrand in France. It was published online on January 4, 2025, in RMD Open.

LIMITATIONS:

The observational design of the study and the low number of herpes zoster events during the follow-up period may have affected the robustness of the findings.

DISCLOSURES:

The authors did not receive any specific grants. Some authors reported having financial relationships with various pharmaceutical companies.

This article was created using several editorial tools, including artificial intelligence, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.

TOPLINE:

The use of valaciclovir as prophylaxis prevents herpes zoster (HZ) in patients with systemic lupus erythematosus (SLE) receiving anifrolumab treatment, with no cases of zoster reported during the follow-up period in patients receiving valaciclovir.

METHODOLOGY:

• Anifrolumab, a human monoclonal antibody binding to type I interferon receptor subunit 1, increases the risk for HZ in patients with SLE; however, specific recommendations to prevent HZ are currently nonexistent for patients with SLE receiving anifrolumab.
• Researchers conducted a multicenter observational study in France from November 2021 to July 2024 to evaluate the prophylactic benefits of valaciclovir in 132 patients with SLE (mean age, 42 years; 92% women) treated with anifrolumab for ≥ 3 months.
• Among these patients, 87 received either 500 mg/d valaciclovir (n = 69) or 1000 mg/d valaciclovir (n = 18) as prophylaxis, whereas 45 did not receive valaciclovir.
• The patients were followed up for a median duration of 234 days under anifrolumab treatment, with monitoring for the development of herpes zoster.

TAKEAWAY:

• The risk for HZ was significantly lower in patients who received valaciclovir than in those who did not (hazard ratio, 0.08; P = .01).
• None of the patients treated with valaciclovir developed HZ during the survey period.
• The frequency of HZ in patients who did not receive valaciclovir increased progressively from 2.2% at 3 months to 6.2% at 6 months, reaching 23% at 12 months.
• None of the reported cases of HZ required hospitalization or led to anifrolumab discontinuation, although one patient developed neuralgia.

IN PRACTICE:

“Prophylactic treatment with valaciclovir is effective for preventing HZ [herpes zoster] infection in SLE patients treated with anifrolumab,” the authors wrote. “This finding is particularly relevant for SLE patients who cannot receive the recombinant HZ vaccine or for whom it is unavailable,” they added.

SOURCE:

The study was led by Ludovic Trefond, MD, PhD, Centre Hospitalier Universitaire de Clermont-Ferrand in France. It was published online on January 4, 2025, in RMD Open.

LIMITATIONS:

The observational design of the study and the low number of herpes zoster events during the follow-up period may have affected the robustness of the findings.

DISCLOSURES:

The authors did not receive any specific grants. Some authors reported having financial relationships with various pharmaceutical companies.

This article was created using several editorial tools, including artificial intelligence, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.

TOPLINE:

The use of valaciclovir as prophylaxis prevents herpes zoster (HZ) in patients with systemic lupus erythematosus (SLE) receiving anifrolumab treatment, with no cases of zoster reported during the follow-up period in patients receiving valaciclovir.

METHODOLOGY:

• Anifrolumab, a human monoclonal antibody binding to type I interferon receptor subunit 1, increases the risk for HZ in patients with SLE; however, specific recommendations to prevent HZ are currently nonexistent for patients with SLE receiving anifrolumab.
• Researchers conducted a multicenter observational study in France from November 2021 to July 2024 to evaluate the prophylactic benefits of valaciclovir in 132 patients with SLE (mean age, 42 years; 92% women) treated with anifrolumab for ≥ 3 months.
• Among these patients, 87 received either 500 mg/d valaciclovir (n = 69) or 1000 mg/d valaciclovir (n = 18) as prophylaxis, whereas 45 did not receive valaciclovir.
• The patients were followed up for a median duration of 234 days under anifrolumab treatment, with monitoring for the development of herpes zoster.

TAKEAWAY:

• The risk for HZ was significantly lower in patients who received valaciclovir than in those who did not (hazard ratio, 0.08; P = .01).
• None of the patients treated with valaciclovir developed HZ during the survey period.
• The frequency of HZ in patients who did not receive valaciclovir increased progressively from 2.2% at 3 months to 6.2% at 6 months, reaching 23% at 12 months.
• None of the reported cases of HZ required hospitalization or led to anifrolumab discontinuation, although one patient developed neuralgia.

IN PRACTICE:

“Prophylactic treatment with valaciclovir is effective for preventing HZ [herpes zoster] infection in SLE patients treated with anifrolumab,” the authors wrote. “This finding is particularly relevant for SLE patients who cannot receive the recombinant HZ vaccine or for whom it is unavailable,” they added.

SOURCE:

The study was led by Ludovic Trefond, MD, PhD, Centre Hospitalier Universitaire de Clermont-Ferrand in France. It was published online on January 4, 2025, in RMD Open.

LIMITATIONS:

The observational design of the study and the low number of herpes zoster events during the follow-up period may have affected the robustness of the findings.

DISCLOSURES:

The authors did not receive any specific grants. Some authors reported having financial relationships with various pharmaceutical companies.

This article was created using several editorial tools, including artificial intelligence, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.

Norovirus cases continue to rise in the United States this winter, at levels higher than the same time period in previous years, according to the latest data from the Centers for Disease Control and Prevention (CDC).

Current data from the CDC’s NoroSTAT monitoring system show 495 reported outbreaks during the period from August 1, 2024, to December 11, 2024, compared with 363 outbreaks during the same period last year. In addition, the total number of norovirus outbreaks in the current season are higher than those reported in the seasonal years: 2012-2020 and 2021-2024.

Circulating strains of norovirus change over time, which can affect disease burden and potential disease severity, Sara Mirza, MD, an epidemiologist in the CDC’s Division of Viral Diseases, said in an interview.

The numbers for the 2024 norovirus season (considered approximately November to April) have reached or exceeded the case numbers seen before the COVID-19 pandemic, Mirza said.

The increase in cases may be caused in part by a new predominant strain of norovirus. “For the fall/winter of 2024-2025 season, genogroup 2, genotype 17, known as GII.17, has become the most detected genotype (strain) in the US among laboratory confirmed outbreaks reported to CDC,” said Mirza. “At this time, there is no indication that GII.17 causes more severe illness or affects one population more than another, but we are continuing to conduct surveillance to assess,” she added.

 

Clinical Takeaways

“Norovirus affects all ages, but young children and older adults are most at risk from more severe outcomes,” said Mirza.

“Clinicians treating older patients for acute gastroenteritis should be aware of these elevated risks and be sure to include norovirus as a potentially serious diagnosis, particularly in vulnerable patients with other diseases and those living in congregate settings, such as nursing homes,” she said.

When treating a patient with norovirus during an outbreak, use soap and water for hand hygiene after caring for patients with suspected or confirmed norovirus gastroenteritis, said Mirza. If norovirus infection is suspected, PPE use is recommended for individuals in the patient care area, she added. 

Although state, local, and territorial health departments are not required to report individual cases of norovirus to the CDC, healthcare providers are encouraged to report all outbreaks of acute gastroenteritis, including suspected outbreaks of norovirus, to the appropriate state, local, or territorial health department, said Mirza. “Health departments are encouraged to report all suspected and confirmed norovirus outbreaks through the National Outbreak Reporting System and CaliciNet,” she added.

“Infection control measures, such as thorough hand washing, cleaning and disinfecting surfaces with bleach, and patient isolation and contact precautions in congregate or healthcare settings are the best ways to prevent norovirus and keep it from spreading to others,” Mirza said.

Remind patients that alcohol-based hand sanitizer is ineffective against norovirus, because the virus’s protective protein shell prevents the alcohol from penetrating and inactivating the virus, Mirza emphasized. “Soap and water work to remove germs from hands,” she said.

 

Cruise Ship Considerations

Cruise ships continue to be sources of increased risk for norovirus, according the CDC. The CDC’s Vessel Sanitation Program (VSP) was created to help the cruise industry prevent public health issues such as norovirus outbreaks, and to provide guidance for actions to take in the event of outbreaks. 

For example, the most recently reported outbreak of norovirus on a cruise ship reported to the VSP was January 4, 2025, and occurred on a Holland America cruise from December 30, 2024, through January 8, 2025. Overall, 4.0% of passengers and 1.0% of crew members reported illness. Following VSP guidance, the ship reported increased cleaning and disinfection procedures and the collection of stool specimens for testing, and isolation of ill passengers and crew.

 

Clinical Perspective

In clinical practice, the number of norovirus cases is significantly exceeding previous years, and the trend seems to be consistent nationwide, David J. Cennimo, MD, associate professor of medicine and pediatrics at Rutgers New Jersey Medical School, Newark, New Jersey, said in an interview.

“Norovirus is incredibly contagious and spreads very quickly, which is how you get entire cruise ships infected at once,” he said. Norovirus is notoriously difficult to disinfect or kill, he added.

One possible contributor to the surge in cases is increased travel, especially during the holiday season, when people are coming together and sharing food, Cennimo noted. “We have seen many infections such as pneumonia return to levels approaching the period before the COVID-19 pandemic,” he said. 

For norovirus prevention, strict attention to sanitation and handwashing is a must at home or when traveling, said Cennimo. For clinicians, it is important to report outbreaks of GI illness so appropriate control measures can be taken, he said.

Visit the CDC’s website on norovirus prevention for more information. 

Mirza and Cennimo had no financial conflicts to disclose.

 

A version of this article appeared on Medscape.com.

Norovirus cases continue to rise in the United States this winter, at levels higher than the same time period in previous years, according to the latest data from the Centers for Disease Control and Prevention (CDC).

Current data from the CDC’s NoroSTAT monitoring system show 495 reported outbreaks during the period from August 1, 2024, to December 11, 2024, compared with 363 outbreaks during the same period last year. In addition, the total number of norovirus outbreaks in the current season are higher than those reported in the seasonal years: 2012-2020 and 2021-2024.

Circulating strains of norovirus change over time, which can affect disease burden and potential disease severity, Sara Mirza, MD, an epidemiologist in the CDC’s Division of Viral Diseases, said in an interview.

The numbers for the 2024 norovirus season (considered approximately November to April) have reached or exceeded the case numbers seen before the COVID-19 pandemic, Mirza said.

The increase in cases may be caused in part by a new predominant strain of norovirus. “For the fall/winter of 2024-2025 season, genogroup 2, genotype 17, known as GII.17, has become the most detected genotype (strain) in the US among laboratory confirmed outbreaks reported to CDC,” said Mirza. “At this time, there is no indication that GII.17 causes more severe illness or affects one population more than another, but we are continuing to conduct surveillance to assess,” she added.

 

Clinical Takeaways

“Norovirus affects all ages, but young children and older adults are most at risk from more severe outcomes,” said Mirza.

“Clinicians treating older patients for acute gastroenteritis should be aware of these elevated risks and be sure to include norovirus as a potentially serious diagnosis, particularly in vulnerable patients with other diseases and those living in congregate settings, such as nursing homes,” she said.

When treating a patient with norovirus during an outbreak, use soap and water for hand hygiene after caring for patients with suspected or confirmed norovirus gastroenteritis, said Mirza. If norovirus infection is suspected, PPE use is recommended for individuals in the patient care area, she added. 

Although state, local, and territorial health departments are not required to report individual cases of norovirus to the CDC, healthcare providers are encouraged to report all outbreaks of acute gastroenteritis, including suspected outbreaks of norovirus, to the appropriate state, local, or territorial health department, said Mirza. “Health departments are encouraged to report all suspected and confirmed norovirus outbreaks through the National Outbreak Reporting System and CaliciNet,” she added.

“Infection control measures, such as thorough hand washing, cleaning and disinfecting surfaces with bleach, and patient isolation and contact precautions in congregate or healthcare settings are the best ways to prevent norovirus and keep it from spreading to others,” Mirza said.

Remind patients that alcohol-based hand sanitizer is ineffective against norovirus, because the virus’s protective protein shell prevents the alcohol from penetrating and inactivating the virus, Mirza emphasized. “Soap and water work to remove germs from hands,” she said.

 

Cruise Ship Considerations

Cruise ships continue to be sources of increased risk for norovirus, according the CDC. The CDC’s Vessel Sanitation Program (VSP) was created to help the cruise industry prevent public health issues such as norovirus outbreaks, and to provide guidance for actions to take in the event of outbreaks. 

For example, the most recently reported outbreak of norovirus on a cruise ship reported to the VSP was January 4, 2025, and occurred on a Holland America cruise from December 30, 2024, through January 8, 2025. Overall, 4.0% of passengers and 1.0% of crew members reported illness. Following VSP guidance, the ship reported increased cleaning and disinfection procedures and the collection of stool specimens for testing, and isolation of ill passengers and crew.

 

Clinical Perspective

In clinical practice, the number of norovirus cases is significantly exceeding previous years, and the trend seems to be consistent nationwide, David J. Cennimo, MD, associate professor of medicine and pediatrics at Rutgers New Jersey Medical School, Newark, New Jersey, said in an interview.

“Norovirus is incredibly contagious and spreads very quickly, which is how you get entire cruise ships infected at once,” he said. Norovirus is notoriously difficult to disinfect or kill, he added.

One possible contributor to the surge in cases is increased travel, especially during the holiday season, when people are coming together and sharing food, Cennimo noted. “We have seen many infections such as pneumonia return to levels approaching the period before the COVID-19 pandemic,” he said. 

For norovirus prevention, strict attention to sanitation and handwashing is a must at home or when traveling, said Cennimo. For clinicians, it is important to report outbreaks of GI illness so appropriate control measures can be taken, he said.

Visit the CDC’s website on norovirus prevention for more information. 

Mirza and Cennimo had no financial conflicts to disclose.

 

A version of this article appeared on Medscape.com.

Norovirus cases continue to rise in the United States this winter, at levels higher than the same time period in previous years, according to the latest data from the Centers for Disease Control and Prevention (CDC).

Current data from the CDC’s NoroSTAT monitoring system show 495 reported outbreaks during the period from August 1, 2024, to December 11, 2024, compared with 363 outbreaks during the same period last year. In addition, the total number of norovirus outbreaks in the current season are higher than those reported in the seasonal years: 2012-2020 and 2021-2024.

Circulating strains of norovirus change over time, which can affect disease burden and potential disease severity, Sara Mirza, MD, an epidemiologist in the CDC’s Division of Viral Diseases, said in an interview.

The numbers for the 2024 norovirus season (considered approximately November to April) have reached or exceeded the case numbers seen before the COVID-19 pandemic, Mirza said.

The increase in cases may be caused in part by a new predominant strain of norovirus. “For the fall/winter of 2024-2025 season, genogroup 2, genotype 17, known as GII.17, has become the most detected genotype (strain) in the US among laboratory confirmed outbreaks reported to CDC,” said Mirza. “At this time, there is no indication that GII.17 causes more severe illness or affects one population more than another, but we are continuing to conduct surveillance to assess,” she added.

 

Clinical Takeaways

“Norovirus affects all ages, but young children and older adults are most at risk from more severe outcomes,” said Mirza.

“Clinicians treating older patients for acute gastroenteritis should be aware of these elevated risks and be sure to include norovirus as a potentially serious diagnosis, particularly in vulnerable patients with other diseases and those living in congregate settings, such as nursing homes,” she said.

When treating a patient with norovirus during an outbreak, use soap and water for hand hygiene after caring for patients with suspected or confirmed norovirus gastroenteritis, said Mirza. If norovirus infection is suspected, PPE use is recommended for individuals in the patient care area, she added. 

Although state, local, and territorial health departments are not required to report individual cases of norovirus to the CDC, healthcare providers are encouraged to report all outbreaks of acute gastroenteritis, including suspected outbreaks of norovirus, to the appropriate state, local, or territorial health department, said Mirza. “Health departments are encouraged to report all suspected and confirmed norovirus outbreaks through the National Outbreak Reporting System and CaliciNet,” she added.

“Infection control measures, such as thorough hand washing, cleaning and disinfecting surfaces with bleach, and patient isolation and contact precautions in congregate or healthcare settings are the best ways to prevent norovirus and keep it from spreading to others,” Mirza said.

Remind patients that alcohol-based hand sanitizer is ineffective against norovirus, because the virus’s protective protein shell prevents the alcohol from penetrating and inactivating the virus, Mirza emphasized. “Soap and water work to remove germs from hands,” she said.

 

Cruise Ship Considerations

Cruise ships continue to be sources of increased risk for norovirus, according the CDC. The CDC’s Vessel Sanitation Program (VSP) was created to help the cruise industry prevent public health issues such as norovirus outbreaks, and to provide guidance for actions to take in the event of outbreaks. 

For example, the most recently reported outbreak of norovirus on a cruise ship reported to the VSP was January 4, 2025, and occurred on a Holland America cruise from December 30, 2024, through January 8, 2025. Overall, 4.0% of passengers and 1.0% of crew members reported illness. Following VSP guidance, the ship reported increased cleaning and disinfection procedures and the collection of stool specimens for testing, and isolation of ill passengers and crew.

 

Clinical Perspective

In clinical practice, the number of norovirus cases is significantly exceeding previous years, and the trend seems to be consistent nationwide, David J. Cennimo, MD, associate professor of medicine and pediatrics at Rutgers New Jersey Medical School, Newark, New Jersey, said in an interview.

“Norovirus is incredibly contagious and spreads very quickly, which is how you get entire cruise ships infected at once,” he said. Norovirus is notoriously difficult to disinfect or kill, he added.

One possible contributor to the surge in cases is increased travel, especially during the holiday season, when people are coming together and sharing food, Cennimo noted. “We have seen many infections such as pneumonia return to levels approaching the period before the COVID-19 pandemic,” he said. 

For norovirus prevention, strict attention to sanitation and handwashing is a must at home or when traveling, said Cennimo. For clinicians, it is important to report outbreaks of GI illness so appropriate control measures can be taken, he said.

Visit the CDC’s website on norovirus prevention for more information. 

Mirza and Cennimo had no financial conflicts to disclose.

 

A version of this article appeared on Medscape.com.

Is there a connection between antibiotics taken before conception and adverse outcomes, such as reduced fertility, miscarriages, and congenital malformations?

A meta-analysis published in the journal eClinicalMedicine suggests a potential link between antibiotics taken before conception and negative outcomes, such as reduced fertility, miscarriages, and congenital malformations. However, a German expert in reproductive toxicology warned against drawing false conclusions.

“It would be fatal if women who want to have children refused necessary antibiotic treatment because they are afraid of infertility, miscarriages, and malformations,” said Wolfgang Paulus, MD, from the Reproductive Toxicology Advisory Center at the University Women’s Hospital in Ulm, Germany. In an interview, the expert criticized not only the authors’ conclusions but also the selection of studies included in the meta-analysis.

 

Confusion Over Use and Exposure

The meta-analysis, conducted by Bekalu Kassie Alemu, PhD, and colleagues from the Department of Obstetrics and Gynecology at The Chinese University of Hong Kong included 15 studies involving over 1.2 million women to examine how preconception antibiotic use affects fertility and pregnancy outcomes. In most studies (n = 11) that were included in the meta-analysis, fertility was examined as an endpoint, primarily in infertile women. One study involved Danish pharmacy employees who handled antibiotics at work.

“Not only was the therapeutic use of antibiotics not examined in this study, but the biological plausibility is completely lacking in this context,” Paulus noted.

The possible effects of preconception antibiotics on miscarriages were investigated in four studies, while two studies focused on congenital malformations as an endpoint.

 

Mixed Findings on Infertility

Regarding infertility, the authors reported abnormalities in macrolides and sulfonamides. Women who had received macrolide antibiotics, such as azithromycin, before conception showed a 35% reduction in fertility rates.

However, Paulus questioned whether this was solely because of macrolides. “Macrolide antibiotics are typically used for chlamydia, and chlamydia infection is a significant factor in women with unmet fertility desires,” he explained. Often, the chlamydia has already caused damage, such as inflammatory processes in the fallopian tubes, contributing to infertility that cannot be resolved by administering antibiotics.

The meta-analysis also showed that women who received sulfonamide before conception had a 2.35-fold increased likelihood of infertility. However, this association is not always one-sided. The results for tetracyclines were heterogeneous; while chlortetracycline appeared to increase the risk for infertility, exposure to oxytetracycline appeared to decrease it.

Treatment with oxytetracycline and beta-lactam antibiotics (except penicillin G) was associated with a 64% lower likelihood of infertility. The authors also found that fluoroquinolone antibiotics were associated with a 13% lower likelihood of infertility.

 

Miscarriage and Malformation Risks

Alemu and colleagues found a significant association between the use of antibiotics before conception and adverse pregnancy outcomes, showing a 34% increased risk for miscarriages and an 85% higher risk for congenital malformations with the use of trimethoprim during preconception. These findings highlight the need for caution regarding antibiotic use in women who are planning to conceive.

“Most antibiotics have half-lives of only a few hours. Therefore, antibiotics administered before conception can hardly have a direct effect on embryonic development,” Paulus noted. He pointed out that extensive data exist on most antibiotic classes included in this meta-analysis regarding childhood anomalies when used during the sensitive phase of organ development. These data do not indicate an increased risk for malformation. Therefore, the increased risk for malformations due to exposure before conception seems less plausible.

Alemu and colleagues assumed that antibiotics might negatively affect female reproductive health by disrupting the gut microbiome. The reasons for the reduced risk for infertility associated with beta-lactams and fluoroquinolones require further investigation. They reach a significant conclusion: “Preconception antibiotics exposure in females increases the risk of infertility, miscarriage, and congenital anomalies.” However, differences exist between the antibiotic classes. While the risk for infertility, spontaneous miscarriages, and congenital malformations increases with the use of macrolide antibiotics, sulfonamides, and trimethoprim, it decreases with the use of beta-lactams and fluoroquinolone antibiotics.

 

Expert Disagreement

“It is conceivable that the use of antibiotics damages the physiological environment, such as in the vaginal area. This may allow unwanted microbes to establish themselves, leading to more adverse outcomes such as infertility and miscarriages,” Paulus acknowledged.

Disruption of the microbiome due to antibiotic therapy could also result in a deficiency in relevant vitamins and trace elements (eg, folic acid), which could contribute to organogenesis disorders. Therefore, it may be beneficial to stabilize the gut and vaginal flora using probiotics after antibiotic treatment.

However, Paulus disagrees with the study conclusions. First, the studies included in the meta-analysis, which were largely observational, did not allow for the direct effect of antibiotics on the examined outcomes. Second, “quinolone antibiotics are highlighted as positive here, as if they were less problematic for patients trying to have children.”

Quinolone antibiotics are generally “frowned upon,” regardless of whether the patient wants to have children, as they can cause damage to the tendons, muscles, joints, and nervous system. They are currently used only as reserve medications.

“Quinolone antibiotics should not be administered during pregnancy, as they have already caused problems in animal studies, and they should not be used before pregnancy because of their side-effect profile,” Paulus stressed.

 

Serious Consequences

Paulus clarified: “The message must not be that women trying to conceive should avoid antibiotics. This applies to treating bacterial infections regardless of fertility desires, as well as for women trying to conceive who have problematic pathogens found in vaginal swabs.”

In these cases, antibiotic treatment is appropriate, and there should be no fear of adverse effects on fertility or pregnancy outcomes. “If antibiotics are not given and the infection worsens, the patient will be even less likely to conceive successfully.”

This story was translated from Medscape’s German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Is there a connection between antibiotics taken before conception and adverse outcomes, such as reduced fertility, miscarriages, and congenital malformations?

A meta-analysis published in the journal eClinicalMedicine suggests a potential link between antibiotics taken before conception and negative outcomes, such as reduced fertility, miscarriages, and congenital malformations. However, a German expert in reproductive toxicology warned against drawing false conclusions.

“It would be fatal if women who want to have children refused necessary antibiotic treatment because they are afraid of infertility, miscarriages, and malformations,” said Wolfgang Paulus, MD, from the Reproductive Toxicology Advisory Center at the University Women’s Hospital in Ulm, Germany. In an interview, the expert criticized not only the authors’ conclusions but also the selection of studies included in the meta-analysis.

 

Confusion Over Use and Exposure

The meta-analysis, conducted by Bekalu Kassie Alemu, PhD, and colleagues from the Department of Obstetrics and Gynecology at The Chinese University of Hong Kong included 15 studies involving over 1.2 million women to examine how preconception antibiotic use affects fertility and pregnancy outcomes. In most studies (n = 11) that were included in the meta-analysis, fertility was examined as an endpoint, primarily in infertile women. One study involved Danish pharmacy employees who handled antibiotics at work.

“Not only was the therapeutic use of antibiotics not examined in this study, but the biological plausibility is completely lacking in this context,” Paulus noted.

The possible effects of preconception antibiotics on miscarriages were investigated in four studies, while two studies focused on congenital malformations as an endpoint.

 

Mixed Findings on Infertility

Regarding infertility, the authors reported abnormalities in macrolides and sulfonamides. Women who had received macrolide antibiotics, such as azithromycin, before conception showed a 35% reduction in fertility rates.

However, Paulus questioned whether this was solely because of macrolides. “Macrolide antibiotics are typically used for chlamydia, and chlamydia infection is a significant factor in women with unmet fertility desires,” he explained. Often, the chlamydia has already caused damage, such as inflammatory processes in the fallopian tubes, contributing to infertility that cannot be resolved by administering antibiotics.

The meta-analysis also showed that women who received sulfonamide before conception had a 2.35-fold increased likelihood of infertility. However, this association is not always one-sided. The results for tetracyclines were heterogeneous; while chlortetracycline appeared to increase the risk for infertility, exposure to oxytetracycline appeared to decrease it.

Treatment with oxytetracycline and beta-lactam antibiotics (except penicillin G) was associated with a 64% lower likelihood of infertility. The authors also found that fluoroquinolone antibiotics were associated with a 13% lower likelihood of infertility.

 

Miscarriage and Malformation Risks

Alemu and colleagues found a significant association between the use of antibiotics before conception and adverse pregnancy outcomes, showing a 34% increased risk for miscarriages and an 85% higher risk for congenital malformations with the use of trimethoprim during preconception. These findings highlight the need for caution regarding antibiotic use in women who are planning to conceive.

“Most antibiotics have half-lives of only a few hours. Therefore, antibiotics administered before conception can hardly have a direct effect on embryonic development,” Paulus noted. He pointed out that extensive data exist on most antibiotic classes included in this meta-analysis regarding childhood anomalies when used during the sensitive phase of organ development. These data do not indicate an increased risk for malformation. Therefore, the increased risk for malformations due to exposure before conception seems less plausible.

Alemu and colleagues assumed that antibiotics might negatively affect female reproductive health by disrupting the gut microbiome. The reasons for the reduced risk for infertility associated with beta-lactams and fluoroquinolones require further investigation. They reach a significant conclusion: “Preconception antibiotics exposure in females increases the risk of infertility, miscarriage, and congenital anomalies.” However, differences exist between the antibiotic classes. While the risk for infertility, spontaneous miscarriages, and congenital malformations increases with the use of macrolide antibiotics, sulfonamides, and trimethoprim, it decreases with the use of beta-lactams and fluoroquinolone antibiotics.

 

Expert Disagreement

“It is conceivable that the use of antibiotics damages the physiological environment, such as in the vaginal area. This may allow unwanted microbes to establish themselves, leading to more adverse outcomes such as infertility and miscarriages,” Paulus acknowledged.

Disruption of the microbiome due to antibiotic therapy could also result in a deficiency in relevant vitamins and trace elements (eg, folic acid), which could contribute to organogenesis disorders. Therefore, it may be beneficial to stabilize the gut and vaginal flora using probiotics after antibiotic treatment.

However, Paulus disagrees with the study conclusions. First, the studies included in the meta-analysis, which were largely observational, did not allow for the direct effect of antibiotics on the examined outcomes. Second, “quinolone antibiotics are highlighted as positive here, as if they were less problematic for patients trying to have children.”

Quinolone antibiotics are generally “frowned upon,” regardless of whether the patient wants to have children, as they can cause damage to the tendons, muscles, joints, and nervous system. They are currently used only as reserve medications.

“Quinolone antibiotics should not be administered during pregnancy, as they have already caused problems in animal studies, and they should not be used before pregnancy because of their side-effect profile,” Paulus stressed.

 

Serious Consequences

Paulus clarified: “The message must not be that women trying to conceive should avoid antibiotics. This applies to treating bacterial infections regardless of fertility desires, as well as for women trying to conceive who have problematic pathogens found in vaginal swabs.”

In these cases, antibiotic treatment is appropriate, and there should be no fear of adverse effects on fertility or pregnancy outcomes. “If antibiotics are not given and the infection worsens, the patient will be even less likely to conceive successfully.”

This story was translated from Medscape’s German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Is there a connection between antibiotics taken before conception and adverse outcomes, such as reduced fertility, miscarriages, and congenital malformations?

A meta-analysis published in the journal eClinicalMedicine suggests a potential link between antibiotics taken before conception and negative outcomes, such as reduced fertility, miscarriages, and congenital malformations. However, a German expert in reproductive toxicology warned against drawing false conclusions.

“It would be fatal if women who want to have children refused necessary antibiotic treatment because they are afraid of infertility, miscarriages, and malformations,” said Wolfgang Paulus, MD, from the Reproductive Toxicology Advisory Center at the University Women’s Hospital in Ulm, Germany. In an interview, the expert criticized not only the authors’ conclusions but also the selection of studies included in the meta-analysis.

 

Confusion Over Use and Exposure

The meta-analysis, conducted by Bekalu Kassie Alemu, PhD, and colleagues from the Department of Obstetrics and Gynecology at The Chinese University of Hong Kong included 15 studies involving over 1.2 million women to examine how preconception antibiotic use affects fertility and pregnancy outcomes. In most studies (n = 11) that were included in the meta-analysis, fertility was examined as an endpoint, primarily in infertile women. One study involved Danish pharmacy employees who handled antibiotics at work.

“Not only was the therapeutic use of antibiotics not examined in this study, but the biological plausibility is completely lacking in this context,” Paulus noted.

The possible effects of preconception antibiotics on miscarriages were investigated in four studies, while two studies focused on congenital malformations as an endpoint.

 

Mixed Findings on Infertility

Regarding infertility, the authors reported abnormalities in macrolides and sulfonamides. Women who had received macrolide antibiotics, such as azithromycin, before conception showed a 35% reduction in fertility rates.

However, Paulus questioned whether this was solely because of macrolides. “Macrolide antibiotics are typically used for chlamydia, and chlamydia infection is a significant factor in women with unmet fertility desires,” he explained. Often, the chlamydia has already caused damage, such as inflammatory processes in the fallopian tubes, contributing to infertility that cannot be resolved by administering antibiotics.

The meta-analysis also showed that women who received sulfonamide before conception had a 2.35-fold increased likelihood of infertility. However, this association is not always one-sided. The results for tetracyclines were heterogeneous; while chlortetracycline appeared to increase the risk for infertility, exposure to oxytetracycline appeared to decrease it.

Treatment with oxytetracycline and beta-lactam antibiotics (except penicillin G) was associated with a 64% lower likelihood of infertility. The authors also found that fluoroquinolone antibiotics were associated with a 13% lower likelihood of infertility.

 

Miscarriage and Malformation Risks

Alemu and colleagues found a significant association between the use of antibiotics before conception and adverse pregnancy outcomes, showing a 34% increased risk for miscarriages and an 85% higher risk for congenital malformations with the use of trimethoprim during preconception. These findings highlight the need for caution regarding antibiotic use in women who are planning to conceive.

“Most antibiotics have half-lives of only a few hours. Therefore, antibiotics administered before conception can hardly have a direct effect on embryonic development,” Paulus noted. He pointed out that extensive data exist on most antibiotic classes included in this meta-analysis regarding childhood anomalies when used during the sensitive phase of organ development. These data do not indicate an increased risk for malformation. Therefore, the increased risk for malformations due to exposure before conception seems less plausible.

Alemu and colleagues assumed that antibiotics might negatively affect female reproductive health by disrupting the gut microbiome. The reasons for the reduced risk for infertility associated with beta-lactams and fluoroquinolones require further investigation. They reach a significant conclusion: “Preconception antibiotics exposure in females increases the risk of infertility, miscarriage, and congenital anomalies.” However, differences exist between the antibiotic classes. While the risk for infertility, spontaneous miscarriages, and congenital malformations increases with the use of macrolide antibiotics, sulfonamides, and trimethoprim, it decreases with the use of beta-lactams and fluoroquinolone antibiotics.

 

Expert Disagreement

“It is conceivable that the use of antibiotics damages the physiological environment, such as in the vaginal area. This may allow unwanted microbes to establish themselves, leading to more adverse outcomes such as infertility and miscarriages,” Paulus acknowledged.

Disruption of the microbiome due to antibiotic therapy could also result in a deficiency in relevant vitamins and trace elements (eg, folic acid), which could contribute to organogenesis disorders. Therefore, it may be beneficial to stabilize the gut and vaginal flora using probiotics after antibiotic treatment.

However, Paulus disagrees with the study conclusions. First, the studies included in the meta-analysis, which were largely observational, did not allow for the direct effect of antibiotics on the examined outcomes. Second, “quinolone antibiotics are highlighted as positive here, as if they were less problematic for patients trying to have children.”

Quinolone antibiotics are generally “frowned upon,” regardless of whether the patient wants to have children, as they can cause damage to the tendons, muscles, joints, and nervous system. They are currently used only as reserve medications.

“Quinolone antibiotics should not be administered during pregnancy, as they have already caused problems in animal studies, and they should not be used before pregnancy because of their side-effect profile,” Paulus stressed.

 

Serious Consequences

Paulus clarified: “The message must not be that women trying to conceive should avoid antibiotics. This applies to treating bacterial infections regardless of fertility desires, as well as for women trying to conceive who have problematic pathogens found in vaginal swabs.”

In these cases, antibiotic treatment is appropriate, and there should be no fear of adverse effects on fertility or pregnancy outcomes. “If antibiotics are not given and the infection worsens, the patient will be even less likely to conceive successfully.”

This story was translated from Medscape’s German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

A few items bring back unpleasant memories of COVID-19, such as masks. However, they are among the simplest and most effective ways to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). If everyone had worn them correctly, the transmission could have been reduced as much as ninefold, according to a theoretical study published in Physical Review E by Richard P. Sear, PhD, from the University of Surrey, Guildford, England.

Study Overcomes Limitations

This study aimed to address the limitations of epidemiological investigations of masks, which can be complex and error-prone. Sear used data obtained from the UK’s COVID-19 app, totaling 7 million contacts, to create a mathematical model of virus transmission, focusing on the correlation between contact duration and infection. The model estimates that if all UK residents had worn masks during every potential exposure, virus transmission would have been approximately nine times lower.

Although this is a mathematical model, it adds to the growing evidence that supports the benefits of masks. Masks are among the best strategies for treating SARS-CoV-2. This conclusion has been supported by several systematic reviews and additional statistical studies. Conversely, the decision to relax and eliminate mask regulations has had consequences that have received little attention.

As expected, removing the mask mandate leads to increased virus transmission, resulting in more hospitalizations and deaths. A 2024 study estimated that in Japan, where cultural factors lead to much higher mask use in public than in Europe, the decline in mask use from 97% of the population in 2022 to 63% in October 2023 may have caused an additional 3500 deaths.

 

Impact Beyond SARS-CoV-2

One remarkable effect of non-pharmaceutical interventions during the pandemic was the probable extinction of an entire influenza strain (B/Yamagata), which could improve future influenza vaccines and significantly reduce the spread of respiratory syncytial virus. While this was not solely caused by masks, it was also influenced by emergency measures such as lockdowns and social distancing. These behavioral changes can positively alter the landscape of infectious diseases.

Masks play a role in reducing influenza transmission during pandemics. Their effectiveness has been supported by several studies and systematic reviews on a wide range of respiratory viruses. A randomized clinical trial involving 4647 Norwegian participants from February to April 2023, published in May 2024 by the British Medical Journal, suggested that wearing a mask reduces the incidence of respiratory symptoms. Specifically, 8.9% of those who wore masks reported respiratory symptoms during the study period compared with 12.2% of those who did not, representing a relative risk reduction of 27%.

Widespread mask use could also protect against other factors such as fine particulate matter, indirectly reducing the risk for various health conditions. A retrospective study involving 7.8 million residents in the Chinese city of Weifang, published in December 2024 by BMC Public Health, suggested that mask use during the pandemic may have also protected the population from pollution, reducing the number of stroke cases by 38.6% over 33 months of follow-up.

Although there are still voices in bioethics calling for the reintroduction of mask mandates in public places, it is unlikely that, barring emergencies, mask mandates are politically and socially acceptable today. Mask use is also considered a politically polarizing topic in several Western countries. Nevertheless, it is worth considering whether, as we move away from the acute phase of the COVID-19 pandemic, we can more objectively promote the use of masks in public places.

Communicating the importance of public health initiatives and persuading people to support them is a well-known challenge. However, scientific literature offers valuable insights. These include encouraging people to rely on rational thinking rather than emotions and providing information on how masks protect those around them. The fact that East Asian cultures tend to have a more positive relationship with the use of masks shows that, in principle, it is possible to make them acceptable. Data from studies suggest that, as we prepare for potential future pandemics, it may be time to move past polarization and reintroduce masks — not as a universal mandate but as an individual choice for many.

This story was translated from Univadis Italy using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article appeared on Medscape.com.

A few items bring back unpleasant memories of COVID-19, such as masks. However, they are among the simplest and most effective ways to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). If everyone had worn them correctly, the transmission could have been reduced as much as ninefold, according to a theoretical study published in Physical Review E by Richard P. Sear, PhD, from the University of Surrey, Guildford, England.

Study Overcomes Limitations

This study aimed to address the limitations of epidemiological investigations of masks, which can be complex and error-prone. Sear used data obtained from the UK’s COVID-19 app, totaling 7 million contacts, to create a mathematical model of virus transmission, focusing on the correlation between contact duration and infection. The model estimates that if all UK residents had worn masks during every potential exposure, virus transmission would have been approximately nine times lower.

Although this is a mathematical model, it adds to the growing evidence that supports the benefits of masks. Masks are among the best strategies for treating SARS-CoV-2. This conclusion has been supported by several systematic reviews and additional statistical studies. Conversely, the decision to relax and eliminate mask regulations has had consequences that have received little attention.

As expected, removing the mask mandate leads to increased virus transmission, resulting in more hospitalizations and deaths. A 2024 study estimated that in Japan, where cultural factors lead to much higher mask use in public than in Europe, the decline in mask use from 97% of the population in 2022 to 63% in October 2023 may have caused an additional 3500 deaths.

 

Impact Beyond SARS-CoV-2

One remarkable effect of non-pharmaceutical interventions during the pandemic was the probable extinction of an entire influenza strain (B/Yamagata), which could improve future influenza vaccines and significantly reduce the spread of respiratory syncytial virus. While this was not solely caused by masks, it was also influenced by emergency measures such as lockdowns and social distancing. These behavioral changes can positively alter the landscape of infectious diseases.

Masks play a role in reducing influenza transmission during pandemics. Their effectiveness has been supported by several studies and systematic reviews on a wide range of respiratory viruses. A randomized clinical trial involving 4647 Norwegian participants from February to April 2023, published in May 2024 by the British Medical Journal, suggested that wearing a mask reduces the incidence of respiratory symptoms. Specifically, 8.9% of those who wore masks reported respiratory symptoms during the study period compared with 12.2% of those who did not, representing a relative risk reduction of 27%.

Widespread mask use could also protect against other factors such as fine particulate matter, indirectly reducing the risk for various health conditions. A retrospective study involving 7.8 million residents in the Chinese city of Weifang, published in December 2024 by BMC Public Health, suggested that mask use during the pandemic may have also protected the population from pollution, reducing the number of stroke cases by 38.6% over 33 months of follow-up.

Although there are still voices in bioethics calling for the reintroduction of mask mandates in public places, it is unlikely that, barring emergencies, mask mandates are politically and socially acceptable today. Mask use is also considered a politically polarizing topic in several Western countries. Nevertheless, it is worth considering whether, as we move away from the acute phase of the COVID-19 pandemic, we can more objectively promote the use of masks in public places.

Communicating the importance of public health initiatives and persuading people to support them is a well-known challenge. However, scientific literature offers valuable insights. These include encouraging people to rely on rational thinking rather than emotions and providing information on how masks protect those around them. The fact that East Asian cultures tend to have a more positive relationship with the use of masks shows that, in principle, it is possible to make them acceptable. Data from studies suggest that, as we prepare for potential future pandemics, it may be time to move past polarization and reintroduce masks — not as a universal mandate but as an individual choice for many.

This story was translated from Univadis Italy using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article appeared on Medscape.com.

A few items bring back unpleasant memories of COVID-19, such as masks. However, they are among the simplest and most effective ways to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). If everyone had worn them correctly, the transmission could have been reduced as much as ninefold, according to a theoretical study published in Physical Review E by Richard P. Sear, PhD, from the University of Surrey, Guildford, England.

Study Overcomes Limitations

This study aimed to address the limitations of epidemiological investigations of masks, which can be complex and error-prone. Sear used data obtained from the UK’s COVID-19 app, totaling 7 million contacts, to create a mathematical model of virus transmission, focusing on the correlation between contact duration and infection. The model estimates that if all UK residents had worn masks during every potential exposure, virus transmission would have been approximately nine times lower.

Although this is a mathematical model, it adds to the growing evidence that supports the benefits of masks. Masks are among the best strategies for treating SARS-CoV-2. This conclusion has been supported by several systematic reviews and additional statistical studies. Conversely, the decision to relax and eliminate mask regulations has had consequences that have received little attention.

As expected, removing the mask mandate leads to increased virus transmission, resulting in more hospitalizations and deaths. A 2024 study estimated that in Japan, where cultural factors lead to much higher mask use in public than in Europe, the decline in mask use from 97% of the population in 2022 to 63% in October 2023 may have caused an additional 3500 deaths.

 

Impact Beyond SARS-CoV-2

One remarkable effect of non-pharmaceutical interventions during the pandemic was the probable extinction of an entire influenza strain (B/Yamagata), which could improve future influenza vaccines and significantly reduce the spread of respiratory syncytial virus. While this was not solely caused by masks, it was also influenced by emergency measures such as lockdowns and social distancing. These behavioral changes can positively alter the landscape of infectious diseases.

Masks play a role in reducing influenza transmission during pandemics. Their effectiveness has been supported by several studies and systematic reviews on a wide range of respiratory viruses. A randomized clinical trial involving 4647 Norwegian participants from February to April 2023, published in May 2024 by the British Medical Journal, suggested that wearing a mask reduces the incidence of respiratory symptoms. Specifically, 8.9% of those who wore masks reported respiratory symptoms during the study period compared with 12.2% of those who did not, representing a relative risk reduction of 27%.

Widespread mask use could also protect against other factors such as fine particulate matter, indirectly reducing the risk for various health conditions. A retrospective study involving 7.8 million residents in the Chinese city of Weifang, published in December 2024 by BMC Public Health, suggested that mask use during the pandemic may have also protected the population from pollution, reducing the number of stroke cases by 38.6% over 33 months of follow-up.

Although there are still voices in bioethics calling for the reintroduction of mask mandates in public places, it is unlikely that, barring emergencies, mask mandates are politically and socially acceptable today. Mask use is also considered a politically polarizing topic in several Western countries. Nevertheless, it is worth considering whether, as we move away from the acute phase of the COVID-19 pandemic, we can more objectively promote the use of masks in public places.

Communicating the importance of public health initiatives and persuading people to support them is a well-known challenge. However, scientific literature offers valuable insights. These include encouraging people to rely on rational thinking rather than emotions and providing information on how masks protect those around them. The fact that East Asian cultures tend to have a more positive relationship with the use of masks shows that, in principle, it is possible to make them acceptable. Data from studies suggest that, as we prepare for potential future pandemics, it may be time to move past polarization and reintroduce masks — not as a universal mandate but as an individual choice for many.

This story was translated from Univadis Italy using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article appeared on Medscape.com.

The pediatrician’s first patient of the day was an 8-year-old boy, accompanied by both of his parents. It was the boy’s third visit in just over a week for fever and left-sided neck swelling, and the family was understandably anxious for answers.

“The antibiotics don’t seem to be working,” the mother explained. “He still has fever every day, as high as 104, and his neck looks just as swollen.”

A quick review of the chart revealed the boy’s initial diagnosis had been bacterial lymphadenitis, for which amoxicillin-clavulanate had been prescribed. Three days later, given lack of clinical improvement, therapy was transitioned to clindamycin. On examination, the boy was febrile and ill-appearing with a 3-cm by 5-cm tender, non-fluctuant swelling over the left sternocleidomastoid muscle. 

 

The pediatrician ran through a quick mental checklist of diagnostic possibilities for his patient’s continued symptoms. Staphylococcal lymphadenitis still seemed possible. Could the boy be infected with methicillin-resistant Staphylococcus aureus that was also clindamycin resistant? Alternately, perhaps the problem was “source control” and the boy had developed an occult neck abscess that needed to be drained. An ultrasound could help sort that out. Finally, the pediatrician considered less common bacterial causes of lymph node swelling and fever. He placed Bartonella henselae, the cause of cat scratch disease, near the top of his list. “I’ve never seen it,” he told the parents, “But we could also consider tularemia.”

Tularemia is a rare zoonotic infection caused by Francisella tularenis. On average, 200 cases of tularemia are reported in the United States each year, and the incidence of disease is increasing, according to a surveillance report released by the Centers for Disease Control and Prevention in December 2023.¹

Between 2011 and 2022, 2462 tularemia cases were reported in the United States. That translated to an average annual incidence of 0.064 per 100,000 population, an increase of 56% compared with 2001-2010. Forty-seven states reported at least one case of tularemia, although half of all reported cases came from four states — Arkansas (18%), Kansas (11%), Missouri (11%), and Oklahoma (10%). The incidence of tularemia was highest in children ages 5-9 years old, older men, and American Indian or Alaska Natives individuals. Although cases occurred year-round, 78% had symptom onset May through September. 

In the United States, most human cases of tularemia have been arthropod borne, transmitted by the bite of an infected tick or deer fly. Infection also can be spread through contact with infected animals or animal tissue, particularly rabbits, hares, muskrats, prairie dogs, and other rodents, including hamsters. Outbreaks of tularemia have occurred among pet store hamsters, and at least one child in the United States developed tularemia after being bitten by a pet hamster.

Tularemia is almost always associated with fever but other clinical manifestations vary by the type of exposure. Ulceroglandular disease occurs after a tick or deer fly bite or after handling an infected animal. An ulcer develops at the site where the bacteria entered the body, along with enlargement of regional lymph nodes. Less commonly, lymph node swelling can occur without the development of an ulcer. If the bacteria enter through the eye, symptoms include conjunctivitis and swelling of pre-auricular lymph nodes. Eating or drinking contaminated food or water is associated with sore throat, mouth ulcers, tonsillitis, and swelling of lymph glands in the neck. Pneumonic tularemia, the most serious form of the disease, typically happens after inhaling bacteria-containing dust or aerosols and is associated with cough, chest pain, and difficulty breathing. Pneumonic tularemia can develop if other forms of tularemia are untreated, and the bacteria spread to the lung.

Back in the exam room, the pediatrician carefully re-examined the boy’s scalp. A 1-cm poorly healing ulcer on the left occiput added support for the diagnosis of ulceroglandular tularemia, the most common form of the disease in children. Serologic testing ultimately confirmed the diagnosis and the boy’s symptoms resolved with treatment.

Gentamicin administered intravenously or intramuscularly is the drug of choice for the treatment of tularemia in children. Ciprofloxacin is considered an alternative but is not approved by the U.S. Food and Drug Administration for this indication.

The pediatrician reported the case of tularemia to his local health department. Tularemia is a nationally notifiable disease in the United States; state health departments report to the CDC through the National Notifiable Diseases Surveillance System. In turn, public health authorities shared information to prevent tularemia. Steps to prevent tick and deer fly bites include the use of an Environmental Protection Agency–registered insect repellent. Individuals who hunt, trap, or skin animals are encouraged to wear gloves when handling animals —especially rabbits, muskrats, and prairie dogs — and cook game meat thoroughly. Tularemia can be inadvertently aerosolized if an infected animal or carcass is run over with a tractor or lawnmower. Checking for carcasses before mowing may reduce the risk.

 

Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She is a member of the AAP’s Committee on Infectious Diseases and one of the lead authors of the AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022-2023. The opinions expressed in this article are her own. Bryant discloses that she has served as an investigator on clinical trials funded by Pfizer, Enanta and Gilead. Email her at [email protected]. (Also [email protected].) 

Reference

1. Rich SN et al. Tularemia—United States, 2011-2022. MMWR Morb Mortal Wkly Rep 2025;73:1152–1156. doi: 

The pediatrician’s first patient of the day was an 8-year-old boy, accompanied by both of his parents. It was the boy’s third visit in just over a week for fever and left-sided neck swelling, and the family was understandably anxious for answers.

“The antibiotics don’t seem to be working,” the mother explained. “He still has fever every day, as high as 104, and his neck looks just as swollen.”

A quick review of the chart revealed the boy’s initial diagnosis had been bacterial lymphadenitis, for which amoxicillin-clavulanate had been prescribed. Three days later, given lack of clinical improvement, therapy was transitioned to clindamycin. On examination, the boy was febrile and ill-appearing with a 3-cm by 5-cm tender, non-fluctuant swelling over the left sternocleidomastoid muscle. 

 

The pediatrician ran through a quick mental checklist of diagnostic possibilities for his patient’s continued symptoms. Staphylococcal lymphadenitis still seemed possible. Could the boy be infected with methicillin-resistant Staphylococcus aureus that was also clindamycin resistant? Alternately, perhaps the problem was “source control” and the boy had developed an occult neck abscess that needed to be drained. An ultrasound could help sort that out. Finally, the pediatrician considered less common bacterial causes of lymph node swelling and fever. He placed Bartonella henselae, the cause of cat scratch disease, near the top of his list. “I’ve never seen it,” he told the parents, “But we could also consider tularemia.”

Tularemia is a rare zoonotic infection caused by Francisella tularenis. On average, 200 cases of tularemia are reported in the United States each year, and the incidence of disease is increasing, according to a surveillance report released by the Centers for Disease Control and Prevention in December 2023.¹

Between 2011 and 2022, 2462 tularemia cases were reported in the United States. That translated to an average annual incidence of 0.064 per 100,000 population, an increase of 56% compared with 2001-2010. Forty-seven states reported at least one case of tularemia, although half of all reported cases came from four states — Arkansas (18%), Kansas (11%), Missouri (11%), and Oklahoma (10%). The incidence of tularemia was highest in children ages 5-9 years old, older men, and American Indian or Alaska Natives individuals. Although cases occurred year-round, 78% had symptom onset May through September. 

In the United States, most human cases of tularemia have been arthropod borne, transmitted by the bite of an infected tick or deer fly. Infection also can be spread through contact with infected animals or animal tissue, particularly rabbits, hares, muskrats, prairie dogs, and other rodents, including hamsters. Outbreaks of tularemia have occurred among pet store hamsters, and at least one child in the United States developed tularemia after being bitten by a pet hamster.

Tularemia is almost always associated with fever but other clinical manifestations vary by the type of exposure. Ulceroglandular disease occurs after a tick or deer fly bite or after handling an infected animal. An ulcer develops at the site where the bacteria entered the body, along with enlargement of regional lymph nodes. Less commonly, lymph node swelling can occur without the development of an ulcer. If the bacteria enter through the eye, symptoms include conjunctivitis and swelling of pre-auricular lymph nodes. Eating or drinking contaminated food or water is associated with sore throat, mouth ulcers, tonsillitis, and swelling of lymph glands in the neck. Pneumonic tularemia, the most serious form of the disease, typically happens after inhaling bacteria-containing dust or aerosols and is associated with cough, chest pain, and difficulty breathing. Pneumonic tularemia can develop if other forms of tularemia are untreated, and the bacteria spread to the lung.

Back in the exam room, the pediatrician carefully re-examined the boy’s scalp. A 1-cm poorly healing ulcer on the left occiput added support for the diagnosis of ulceroglandular tularemia, the most common form of the disease in children. Serologic testing ultimately confirmed the diagnosis and the boy’s symptoms resolved with treatment.

Gentamicin administered intravenously or intramuscularly is the drug of choice for the treatment of tularemia in children. Ciprofloxacin is considered an alternative but is not approved by the U.S. Food and Drug Administration for this indication.

The pediatrician reported the case of tularemia to his local health department. Tularemia is a nationally notifiable disease in the United States; state health departments report to the CDC through the National Notifiable Diseases Surveillance System. In turn, public health authorities shared information to prevent tularemia. Steps to prevent tick and deer fly bites include the use of an Environmental Protection Agency–registered insect repellent. Individuals who hunt, trap, or skin animals are encouraged to wear gloves when handling animals —especially rabbits, muskrats, and prairie dogs — and cook game meat thoroughly. Tularemia can be inadvertently aerosolized if an infected animal or carcass is run over with a tractor or lawnmower. Checking for carcasses before mowing may reduce the risk.

 

Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She is a member of the AAP’s Committee on Infectious Diseases and one of the lead authors of the AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022-2023. The opinions expressed in this article are her own. Bryant discloses that she has served as an investigator on clinical trials funded by Pfizer, Enanta and Gilead. Email her at [email protected]. (Also [email protected].) 

Reference

1. Rich SN et al. Tularemia—United States, 2011-2022. MMWR Morb Mortal Wkly Rep 2025;73:1152–1156. doi: 

The pediatrician’s first patient of the day was an 8-year-old boy, accompanied by both of his parents. It was the boy’s third visit in just over a week for fever and left-sided neck swelling, and the family was understandably anxious for answers.

“The antibiotics don’t seem to be working,” the mother explained. “He still has fever every day, as high as 104, and his neck looks just as swollen.”

A quick review of the chart revealed the boy’s initial diagnosis had been bacterial lymphadenitis, for which amoxicillin-clavulanate had been prescribed. Three days later, given lack of clinical improvement, therapy was transitioned to clindamycin. On examination, the boy was febrile and ill-appearing with a 3-cm by 5-cm tender, non-fluctuant swelling over the left sternocleidomastoid muscle. 

 

The pediatrician ran through a quick mental checklist of diagnostic possibilities for his patient’s continued symptoms. Staphylococcal lymphadenitis still seemed possible. Could the boy be infected with methicillin-resistant Staphylococcus aureus that was also clindamycin resistant? Alternately, perhaps the problem was “source control” and the boy had developed an occult neck abscess that needed to be drained. An ultrasound could help sort that out. Finally, the pediatrician considered less common bacterial causes of lymph node swelling and fever. He placed Bartonella henselae, the cause of cat scratch disease, near the top of his list. “I’ve never seen it,” he told the parents, “But we could also consider tularemia.”

Tularemia is a rare zoonotic infection caused by Francisella tularenis. On average, 200 cases of tularemia are reported in the United States each year, and the incidence of disease is increasing, according to a surveillance report released by the Centers for Disease Control and Prevention in December 2023.¹

Between 2011 and 2022, 2462 tularemia cases were reported in the United States. That translated to an average annual incidence of 0.064 per 100,000 population, an increase of 56% compared with 2001-2010. Forty-seven states reported at least one case of tularemia, although half of all reported cases came from four states — Arkansas (18%), Kansas (11%), Missouri (11%), and Oklahoma (10%). The incidence of tularemia was highest in children ages 5-9 years old, older men, and American Indian or Alaska Natives individuals. Although cases occurred year-round, 78% had symptom onset May through September. 

In the United States, most human cases of tularemia have been arthropod borne, transmitted by the bite of an infected tick or deer fly. Infection also can be spread through contact with infected animals or animal tissue, particularly rabbits, hares, muskrats, prairie dogs, and other rodents, including hamsters. Outbreaks of tularemia have occurred among pet store hamsters, and at least one child in the United States developed tularemia after being bitten by a pet hamster.

Tularemia is almost always associated with fever but other clinical manifestations vary by the type of exposure. Ulceroglandular disease occurs after a tick or deer fly bite or after handling an infected animal. An ulcer develops at the site where the bacteria entered the body, along with enlargement of regional lymph nodes. Less commonly, lymph node swelling can occur without the development of an ulcer. If the bacteria enter through the eye, symptoms include conjunctivitis and swelling of pre-auricular lymph nodes. Eating or drinking contaminated food or water is associated with sore throat, mouth ulcers, tonsillitis, and swelling of lymph glands in the neck. Pneumonic tularemia, the most serious form of the disease, typically happens after inhaling bacteria-containing dust or aerosols and is associated with cough, chest pain, and difficulty breathing. Pneumonic tularemia can develop if other forms of tularemia are untreated, and the bacteria spread to the lung.

Back in the exam room, the pediatrician carefully re-examined the boy’s scalp. A 1-cm poorly healing ulcer on the left occiput added support for the diagnosis of ulceroglandular tularemia, the most common form of the disease in children. Serologic testing ultimately confirmed the diagnosis and the boy’s symptoms resolved with treatment.

Gentamicin administered intravenously or intramuscularly is the drug of choice for the treatment of tularemia in children. Ciprofloxacin is considered an alternative but is not approved by the U.S. Food and Drug Administration for this indication.

The pediatrician reported the case of tularemia to his local health department. Tularemia is a nationally notifiable disease in the United States; state health departments report to the CDC through the National Notifiable Diseases Surveillance System. In turn, public health authorities shared information to prevent tularemia. Steps to prevent tick and deer fly bites include the use of an Environmental Protection Agency–registered insect repellent. Individuals who hunt, trap, or skin animals are encouraged to wear gloves when handling animals —especially rabbits, muskrats, and prairie dogs — and cook game meat thoroughly. Tularemia can be inadvertently aerosolized if an infected animal or carcass is run over with a tractor or lawnmower. Checking for carcasses before mowing may reduce the risk.

 

Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She is a member of the AAP’s Committee on Infectious Diseases and one of the lead authors of the AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022-2023. The opinions expressed in this article are her own. Bryant discloses that she has served as an investigator on clinical trials funded by Pfizer, Enanta and Gilead. Email her at [email protected]. (Also [email protected].) 

Reference

1. Rich SN et al. Tularemia—United States, 2011-2022. MMWR Morb Mortal Wkly Rep 2025;73:1152–1156. doi: 

Mild traumatic brain injury (TBI) may reactivate latent herpes simplex virus type 1 (HSV-1) in the brain and contribute to neurodegeneration and development of Alzheimer’s disease pathology, a new study suggested.

Using a three-dimensional (3D) human brain tissue model, researchers observed that quiescent HSV-1 can be reactivated by a mechanical jolt mimicking concussion, leading to signature markers of Alzheimer’s disease, including neuroinflammation and production of amyloid beta and phosphorylated tau (p-tau) and gliosis — a phenotype made worse by repeated head injury.

“This opens the question as to whether antiviral drugs or anti-inflammatory agents might be useful as early preventive treatments after head trauma to stop HSV-1 activation in its tracks and lower the risk of Alzheimer’s disease,” lead investigator Dana Cairns, PhD, with the Department of Biomedical Engineering at Tufts University, Medford, Massachusetts, said in a statement.

But outside experts urged caution in drawing any firm conclusions, pending further study.

The study was published online in the journal Science Signaling.

 

HSV-1: A Major Alzheimer’s Disease Risk Factor?

TBI is a major risk factor for Alzheimer’s disease and dementia, but the pathways in the brain leading from TBI to dementia are unknown.

HSV-1 is found in over 80% of people; varicella zoster virus (VZV) is found in about 95%. Both viruses are known to enter the brain and lay dormant in neurons and glial cells. Prior evidence indicates that HSV-1 in the brain of APOE-ε4 carriers confers a strong risk for Alzheimer’s disease.

A number of years ago, the team created a 3D model of human brain tissue to study the link between TBI, the viruses, and dementia. The model is 6 mm wide, shaped like a donut, and made of a spongy material of silk protein and collagen saturated with neural stem cells. The cells mature into neurons, communicate with each other, and form a network that mimics the brain environment.

In an earlier study using the model quiescently infected with HSV-1, Cairns and colleagues found that subsequent exposure to VZV created the inflammatory conditions that led to reactivation of HSV-1.

This led them to wonder what would happen if they subjected the brain tissue model to a physical disruption akin to a concussion. Would HSV-1 wake up and start the process of neurodegeneration?

To investigate, they examined the effects of one or more controlled blows to the 3D human brain tissue model in the absence or presence of quiescent HSV-1 infection.

After repeated, mild controlled blows, researchers found that the latently infected 3D brain tissue displayed reactivated HSV-1 and the production and accumulation of amyloid beta and p-tau — which promotes neurodegeneration. The blows also activated gliosis, which is associated with destructive neuroinflammation.

These effects are collectively associated with Alzheimer’s disease, dementia, and chronic traumatic encephalopathy, they pointed out, and were increased with additional injury but were absent in tissue not infected with HSV-1.

“These data suggest that HSV-1 in the brain is pivotal in increasing the risk of Alzheimer’s disease, as other recent studies using cerebral organoids have suggested,” the researchers wrote.

They propose that following brain injury, “whether by infection or mechanical damage, the resulting inflammation induces HSV-1 reactivation in the brain leading to the development of Alzheimer’s disease/dementia and that HSV-1 is a major cause of the disease, especially in APOE4 carriers.”

Future studies should investigate “possible ways of mitigating or stopping the damage caused by head injury, thereby reducing subsequent development of Alzheimer’s disease by implementing efforts to prevent the reactivation of virus in brain such as anti-inflammatory and/or antiviral treatment post-injury,” researchers suggested.

 

Outside Experts Weigh in

Several outside experts offered perspective on the study in a statement from the UK nonprofit Science Media Centre.

Tara Spires-Jones, PhD, president of the British Neuroscience Association and group leader at the UK Dementia Research Institute, London, England, said that, while the study is interesting, there are limitations.

“The increase in Alzheimer’s-like brain changes in these latent virus-containing cells subjected to injury does not resemble the pathology that is found in the brain of people with Alzheimer’s disease,” Spires-Jones noted.

“These experiments were also in cells grown in artificial conditions without important Alzheimer’s-related factors such as age and blood vessel changes. Finally, these experiments were repeated in a small number of experimental replicates (three times per experiment), so these results will need to be confirmed in more relevant biological systems with larger studies to be sure there is a biological link between latent herpes simplex virus type 1, brain injury, and Alzheimer’s pathology,” Spires-Jones cautioned.

Robert Howard, MD, MRCPsych, University College London (UCL) Division of Psychiatry, said the study suggests a possible mechanism for the association between HSV-1, brain injury, and Alzheimer’s disease.

“However, as so often in science, it is very important to bear in mind that association does not mean causation. Much more research will be needed before this can be seriously considered a plausible mechanism for the development of dementia,” Howard cautioned.

“Avoidance of brain injuries, such as those encountered in some contact sports, is already known to be an important way to prevent dementia, and I’m unconvinced that this reflects anything more complicated than mechanical damage causing death of brain cells,” he added.

Jennifer Pocock, PhD, with UCL Queen Square Institute of Neurology, noted the role of microglia, which are activated by mild and repetitive TBI, isn’t addressed in the study.

“This paper seems to suggest that only astrocytes contribute to the reported neuroinflammation in brain tissue. Also, the inclusion of APOE3/4 is not clearly defined. Because of this, the findings are likely to represent an over interpretation for the ‘real world’ as the inclusion of microglia may negate or accentuate them, depending on the severity of the TBI,” Pocock said.

The study was funded by the US Army Research Office and Department of Defense. The authors have declared no relevant conflicts of interest. Spires-Jones and Howard had no relevant disclosures related to this study. Pocock has received research funding from AstraZeneca and Daiichi Sankyo.

A version of this article appeared on Medscape.com.

Mild traumatic brain injury (TBI) may reactivate latent herpes simplex virus type 1 (HSV-1) in the brain and contribute to neurodegeneration and development of Alzheimer’s disease pathology, a new study suggested.

Using a three-dimensional (3D) human brain tissue model, researchers observed that quiescent HSV-1 can be reactivated by a mechanical jolt mimicking concussion, leading to signature markers of Alzheimer’s disease, including neuroinflammation and production of amyloid beta and phosphorylated tau (p-tau) and gliosis — a phenotype made worse by repeated head injury.

“This opens the question as to whether antiviral drugs or anti-inflammatory agents might be useful as early preventive treatments after head trauma to stop HSV-1 activation in its tracks and lower the risk of Alzheimer’s disease,” lead investigator Dana Cairns, PhD, with the Department of Biomedical Engineering at Tufts University, Medford, Massachusetts, said in a statement.

But outside experts urged caution in drawing any firm conclusions, pending further study.

The study was published online in the journal Science Signaling.

 

HSV-1: A Major Alzheimer’s Disease Risk Factor?

TBI is a major risk factor for Alzheimer’s disease and dementia, but the pathways in the brain leading from TBI to dementia are unknown.

HSV-1 is found in over 80% of people; varicella zoster virus (VZV) is found in about 95%. Both viruses are known to enter the brain and lay dormant in neurons and glial cells. Prior evidence indicates that HSV-1 in the brain of APOE-ε4 carriers confers a strong risk for Alzheimer’s disease.

A number of years ago, the team created a 3D model of human brain tissue to study the link between TBI, the viruses, and dementia. The model is 6 mm wide, shaped like a donut, and made of a spongy material of silk protein and collagen saturated with neural stem cells. The cells mature into neurons, communicate with each other, and form a network that mimics the brain environment.

In an earlier study using the model quiescently infected with HSV-1, Cairns and colleagues found that subsequent exposure to VZV created the inflammatory conditions that led to reactivation of HSV-1.

This led them to wonder what would happen if they subjected the brain tissue model to a physical disruption akin to a concussion. Would HSV-1 wake up and start the process of neurodegeneration?

To investigate, they examined the effects of one or more controlled blows to the 3D human brain tissue model in the absence or presence of quiescent HSV-1 infection.

After repeated, mild controlled blows, researchers found that the latently infected 3D brain tissue displayed reactivated HSV-1 and the production and accumulation of amyloid beta and p-tau — which promotes neurodegeneration. The blows also activated gliosis, which is associated with destructive neuroinflammation.

These effects are collectively associated with Alzheimer’s disease, dementia, and chronic traumatic encephalopathy, they pointed out, and were increased with additional injury but were absent in tissue not infected with HSV-1.

“These data suggest that HSV-1 in the brain is pivotal in increasing the risk of Alzheimer’s disease, as other recent studies using cerebral organoids have suggested,” the researchers wrote.

They propose that following brain injury, “whether by infection or mechanical damage, the resulting inflammation induces HSV-1 reactivation in the brain leading to the development of Alzheimer’s disease/dementia and that HSV-1 is a major cause of the disease, especially in APOE4 carriers.”

Future studies should investigate “possible ways of mitigating or stopping the damage caused by head injury, thereby reducing subsequent development of Alzheimer’s disease by implementing efforts to prevent the reactivation of virus in brain such as anti-inflammatory and/or antiviral treatment post-injury,” researchers suggested.

 

Outside Experts Weigh in

Several outside experts offered perspective on the study in a statement from the UK nonprofit Science Media Centre.

Tara Spires-Jones, PhD, president of the British Neuroscience Association and group leader at the UK Dementia Research Institute, London, England, said that, while the study is interesting, there are limitations.

“The increase in Alzheimer’s-like brain changes in these latent virus-containing cells subjected to injury does not resemble the pathology that is found in the brain of people with Alzheimer’s disease,” Spires-Jones noted.

“These experiments were also in cells grown in artificial conditions without important Alzheimer’s-related factors such as age and blood vessel changes. Finally, these experiments were repeated in a small number of experimental replicates (three times per experiment), so these results will need to be confirmed in more relevant biological systems with larger studies to be sure there is a biological link between latent herpes simplex virus type 1, brain injury, and Alzheimer’s pathology,” Spires-Jones cautioned.

Robert Howard, MD, MRCPsych, University College London (UCL) Division of Psychiatry, said the study suggests a possible mechanism for the association between HSV-1, brain injury, and Alzheimer’s disease.

“However, as so often in science, it is very important to bear in mind that association does not mean causation. Much more research will be needed before this can be seriously considered a plausible mechanism for the development of dementia,” Howard cautioned.

“Avoidance of brain injuries, such as those encountered in some contact sports, is already known to be an important way to prevent dementia, and I’m unconvinced that this reflects anything more complicated than mechanical damage causing death of brain cells,” he added.

Jennifer Pocock, PhD, with UCL Queen Square Institute of Neurology, noted the role of microglia, which are activated by mild and repetitive TBI, isn’t addressed in the study.

“This paper seems to suggest that only astrocytes contribute to the reported neuroinflammation in brain tissue. Also, the inclusion of APOE3/4 is not clearly defined. Because of this, the findings are likely to represent an over interpretation for the ‘real world’ as the inclusion of microglia may negate or accentuate them, depending on the severity of the TBI,” Pocock said.

The study was funded by the US Army Research Office and Department of Defense. The authors have declared no relevant conflicts of interest. Spires-Jones and Howard had no relevant disclosures related to this study. Pocock has received research funding from AstraZeneca and Daiichi Sankyo.

A version of this article appeared on Medscape.com.

Mild traumatic brain injury (TBI) may reactivate latent herpes simplex virus type 1 (HSV-1) in the brain and contribute to neurodegeneration and development of Alzheimer’s disease pathology, a new study suggested.

Using a three-dimensional (3D) human brain tissue model, researchers observed that quiescent HSV-1 can be reactivated by a mechanical jolt mimicking concussion, leading to signature markers of Alzheimer’s disease, including neuroinflammation and production of amyloid beta and phosphorylated tau (p-tau) and gliosis — a phenotype made worse by repeated head injury.

“This opens the question as to whether antiviral drugs or anti-inflammatory agents might be useful as early preventive treatments after head trauma to stop HSV-1 activation in its tracks and lower the risk of Alzheimer’s disease,” lead investigator Dana Cairns, PhD, with the Department of Biomedical Engineering at Tufts University, Medford, Massachusetts, said in a statement.

But outside experts urged caution in drawing any firm conclusions, pending further study.

The study was published online in the journal Science Signaling.

 

HSV-1: A Major Alzheimer’s Disease Risk Factor?

TBI is a major risk factor for Alzheimer’s disease and dementia, but the pathways in the brain leading from TBI to dementia are unknown.

HSV-1 is found in over 80% of people; varicella zoster virus (VZV) is found in about 95%. Both viruses are known to enter the brain and lay dormant in neurons and glial cells. Prior evidence indicates that HSV-1 in the brain of APOE-ε4 carriers confers a strong risk for Alzheimer’s disease.

A number of years ago, the team created a 3D model of human brain tissue to study the link between TBI, the viruses, and dementia. The model is 6 mm wide, shaped like a donut, and made of a spongy material of silk protein and collagen saturated with neural stem cells. The cells mature into neurons, communicate with each other, and form a network that mimics the brain environment.

In an earlier study using the model quiescently infected with HSV-1, Cairns and colleagues found that subsequent exposure to VZV created the inflammatory conditions that led to reactivation of HSV-1.

This led them to wonder what would happen if they subjected the brain tissue model to a physical disruption akin to a concussion. Would HSV-1 wake up and start the process of neurodegeneration?

To investigate, they examined the effects of one or more controlled blows to the 3D human brain tissue model in the absence or presence of quiescent HSV-1 infection.

After repeated, mild controlled blows, researchers found that the latently infected 3D brain tissue displayed reactivated HSV-1 and the production and accumulation of amyloid beta and p-tau — which promotes neurodegeneration. The blows also activated gliosis, which is associated with destructive neuroinflammation.

These effects are collectively associated with Alzheimer’s disease, dementia, and chronic traumatic encephalopathy, they pointed out, and were increased with additional injury but were absent in tissue not infected with HSV-1.

“These data suggest that HSV-1 in the brain is pivotal in increasing the risk of Alzheimer’s disease, as other recent studies using cerebral organoids have suggested,” the researchers wrote.

They propose that following brain injury, “whether by infection or mechanical damage, the resulting inflammation induces HSV-1 reactivation in the brain leading to the development of Alzheimer’s disease/dementia and that HSV-1 is a major cause of the disease, especially in APOE4 carriers.”

Future studies should investigate “possible ways of mitigating or stopping the damage caused by head injury, thereby reducing subsequent development of Alzheimer’s disease by implementing efforts to prevent the reactivation of virus in brain such as anti-inflammatory and/or antiviral treatment post-injury,” researchers suggested.

 

Outside Experts Weigh in

Several outside experts offered perspective on the study in a statement from the UK nonprofit Science Media Centre.

Tara Spires-Jones, PhD, president of the British Neuroscience Association and group leader at the UK Dementia Research Institute, London, England, said that, while the study is interesting, there are limitations.

“The increase in Alzheimer’s-like brain changes in these latent virus-containing cells subjected to injury does not resemble the pathology that is found in the brain of people with Alzheimer’s disease,” Spires-Jones noted.

“These experiments were also in cells grown in artificial conditions without important Alzheimer’s-related factors such as age and blood vessel changes. Finally, these experiments were repeated in a small number of experimental replicates (three times per experiment), so these results will need to be confirmed in more relevant biological systems with larger studies to be sure there is a biological link between latent herpes simplex virus type 1, brain injury, and Alzheimer’s pathology,” Spires-Jones cautioned.

Robert Howard, MD, MRCPsych, University College London (UCL) Division of Psychiatry, said the study suggests a possible mechanism for the association between HSV-1, brain injury, and Alzheimer’s disease.

“However, as so often in science, it is very important to bear in mind that association does not mean causation. Much more research will be needed before this can be seriously considered a plausible mechanism for the development of dementia,” Howard cautioned.

“Avoidance of brain injuries, such as those encountered in some contact sports, is already known to be an important way to prevent dementia, and I’m unconvinced that this reflects anything more complicated than mechanical damage causing death of brain cells,” he added.

Jennifer Pocock, PhD, with UCL Queen Square Institute of Neurology, noted the role of microglia, which are activated by mild and repetitive TBI, isn’t addressed in the study.

“This paper seems to suggest that only astrocytes contribute to the reported neuroinflammation in brain tissue. Also, the inclusion of APOE3/4 is not clearly defined. Because of this, the findings are likely to represent an over interpretation for the ‘real world’ as the inclusion of microglia may negate or accentuate them, depending on the severity of the TBI,” Pocock said.

The study was funded by the US Army Research Office and Department of Defense. The authors have declared no relevant conflicts of interest. Spires-Jones and Howard had no relevant disclosures related to this study. Pocock has received research funding from AstraZeneca and Daiichi Sankyo.

A version of this article appeared on Medscape.com.

Almost 70 years after the discovery of the respiratory syncytial virus (RSV), vaccines and preventive treatments are giving babies a chance to beat the potentially deadly childhood infection.

As doctors turn to monoclonal antibody therapies and governments plan vaccination programs, clinical researchers are asking whether these measures will reduce the spread of the virus. Will fewer babies die from RSV, and fewer children develop permanent wheezing?

Recent studies offer clues.

Fabio Midulla, an associate professor of pediatrics at Sapienza University of Rome in Rome, Italy, said that the pharmaceutical industry is poised to push governments to use vaccines and monoclonal antibodies for even more children. “Such a push might work,” he said at the European Respiratory Society (ERS) 2024 Congress, “given that several studies have already demonstrated that their use can improve outcomes for children who do become infected and reduce societal costs by reducing hospitalizations.”

But Mariëlle WH Pijnenburg, a pulmonary specialist at Erasmus University Rotterdam in the Netherlands, said at the Congress that greater rollout would require governments to force industry to lower prices. If treatments remain beyond the reach of lower-income countries — where the burden of RSV is the greatest — the death toll from this common childhood infection will remain stubbornly high, and the prospect of global elimination will remain forever out of reach, she said.

New Tools in the Fight Against RSV

Nirsevimab, a long-acting monoclonal antibody given to newborns to prevent severe infection, was approved by the European Medicines Agency (EMA) in October 2022 and the US Food and Drug Administration (FDA) in July 2023. And Abrysvo, a vaccine given to older adults and pregnant women to stop them from passing the virus to babies from birth through 6 months of age, was approved by the FDA and the EMA in 2023.

RSV is responsible for over 33 million lung infections in children younger than 5 years annually, with more than 4 million hospitalizations and nearly 200,000 deaths. According to the Centers for Disease Control and Prevention, every year, 2.1 million children younger than 5 years old visit a healthcare provider because of an RSV infection and between 58,000 and 80,000 children younger than 5 years old are hospitalized in the United States. The burden of severe RSV disease is also high among adults, with an estimated 123,000-193,000 hospitalizations, 24,400-34,900 ICU admissions, and 4680-8620 in-hospital deaths occurring annually among US adults.

While the virus affects all age groups, it is particularly severe in infants, swelling their airways and causing them to struggle for breath. Infection in infancy can lead to later complications, such as the development of wheezing, a condition that causes breathlessness and a feeling of tightening in the chest, and possibly also asthma.

Studies have shown that children and preterm infants infected with RSV who were given monoclonal antibodies experienced less post-infection wheezing, suggesting that RSV prophylaxis could prevent the development of wheezing bronchitis.

A study conducted in Galicia, Spain, showed that only 0.3% of infants who received prophylaxis with Nirsevimab were hospitalized for RSV-related lower respiratory tract infections. “This is very promising,” Yvonne Maldonado, MD, professor of pediatrics and epidemiology and population health at Stanford University in Stanford, California, told Medscape Medical News. “But this virus is ubiquitous. It’s found everywhere. It comes around every winter season. And immunity is not long-lasting.”

Older children who are not receiving monoclonal antibodies still experience RSV-related hospitalizations, suggesting the virus continues to circulate at high enough levels in the community. “The vaccine and monoclonal antibodies can reduce the risk of hospitalization and more severe disease in young kids, but they won’t eliminate the virus,” Maldonado said. “Right now, the goal is to prevent serious infection, not to prevent the spread of the virus completely.”

Expanding Access to RSV Prevention in Low-Income Countries

Currently, the RSV vaccine and monoclonal antibodies are only given in the United States, Europe, United Kingdom, and Canada to newborns, children at risk for severe disease, and pregnant women. However, Midulla said that pharmaceutical companies are pushing to broaden the rollout to a broader population within these countries. Yet, he said, over 99% of RSV infection–related deaths occur in the Global South.

No pharmaceutical company has sought approval in low-income countries such as those in Africa. “Unless they see there being a market in a country, they’re not going to go through the onerous process of getting [a vaccine] licensed,” Shabir Madhi, dean of the faculty of health sciences and a professor of vaccinology at the University of the Witwatersrand, Johannesburg, South Africa, told Medscape Medical News.

He highlighted that almost 50% of RSV-related deaths occur in African children younger than 5 years, despite these children comprising just one fifth of the global under-5 population. The high burden of RSV mortality in the Global South is mainly due to poor access to healthcare and supportive treatments, such as supplemental oxygen, which can help children recover from severe RSV infection.

Companies are unlikely to pursue regulatory approval and licensing in low- and middle-income countries until GAVI, the global vaccine alliance, commits to procuring and funding the vaccines for these regions. GAVI’s decision would provide the necessary market incentive for manufacturers to seek approval.

Madhi suggested that GAVI’s decision on RSV vaccine procurement is imminent, likely early next year, following the World Health Organization’s Strategic Advisory Group of Experts on Immunization recommendation to vaccinate all pregnant women with the RSV vaccine, regardless of whether they are in high-income or low-income countries.

Nevertheless, even if vaccines become available, many African countries may still struggle to afford them. Madhi said that these countries would likely depend on GAVI and organizations like UNICEF to procure the vaccines at affordable prices. “The unfortunate reality is that many countries — especially in Africa — still wouldn’t be able to afford it, even if the vaccine cost as little as $5,” said Madhi. “But that’s where they would have the greatest impact.”

Midulla, Pijnenburg reported no relevant financial relationships. Madhi’s research unit, the Vaccines and Infectious Disease Analytics Unit, was involved in the clinical trials for the Pfizer RSV vaccine, the GSK RSV vaccine (which was terminated), as well as the MEDLEY trial of palivizumab. All funding for these studies went to his institution, the University of the Witwatersrand. Maldonado was Stanford principal investigator for the Pfizer RSV vaccine.
 

A version of this article appeared on Medscape.com.

Almost 70 years after the discovery of the respiratory syncytial virus (RSV), vaccines and preventive treatments are giving babies a chance to beat the potentially deadly childhood infection.

As doctors turn to monoclonal antibody therapies and governments plan vaccination programs, clinical researchers are asking whether these measures will reduce the spread of the virus. Will fewer babies die from RSV, and fewer children develop permanent wheezing?

Recent studies offer clues.

Fabio Midulla, an associate professor of pediatrics at Sapienza University of Rome in Rome, Italy, said that the pharmaceutical industry is poised to push governments to use vaccines and monoclonal antibodies for even more children. “Such a push might work,” he said at the European Respiratory Society (ERS) 2024 Congress, “given that several studies have already demonstrated that their use can improve outcomes for children who do become infected and reduce societal costs by reducing hospitalizations.”

But Mariëlle WH Pijnenburg, a pulmonary specialist at Erasmus University Rotterdam in the Netherlands, said at the Congress that greater rollout would require governments to force industry to lower prices. If treatments remain beyond the reach of lower-income countries — where the burden of RSV is the greatest — the death toll from this common childhood infection will remain stubbornly high, and the prospect of global elimination will remain forever out of reach, she said.

New Tools in the Fight Against RSV

Nirsevimab, a long-acting monoclonal antibody given to newborns to prevent severe infection, was approved by the European Medicines Agency (EMA) in October 2022 and the US Food and Drug Administration (FDA) in July 2023. And Abrysvo, a vaccine given to older adults and pregnant women to stop them from passing the virus to babies from birth through 6 months of age, was approved by the FDA and the EMA in 2023.

RSV is responsible for over 33 million lung infections in children younger than 5 years annually, with more than 4 million hospitalizations and nearly 200,000 deaths. According to the Centers for Disease Control and Prevention, every year, 2.1 million children younger than 5 years old visit a healthcare provider because of an RSV infection and between 58,000 and 80,000 children younger than 5 years old are hospitalized in the United States. The burden of severe RSV disease is also high among adults, with an estimated 123,000-193,000 hospitalizations, 24,400-34,900 ICU admissions, and 4680-8620 in-hospital deaths occurring annually among US adults.

While the virus affects all age groups, it is particularly severe in infants, swelling their airways and causing them to struggle for breath. Infection in infancy can lead to later complications, such as the development of wheezing, a condition that causes breathlessness and a feeling of tightening in the chest, and possibly also asthma.

Studies have shown that children and preterm infants infected with RSV who were given monoclonal antibodies experienced less post-infection wheezing, suggesting that RSV prophylaxis could prevent the development of wheezing bronchitis.

A study conducted in Galicia, Spain, showed that only 0.3% of infants who received prophylaxis with Nirsevimab were hospitalized for RSV-related lower respiratory tract infections. “This is very promising,” Yvonne Maldonado, MD, professor of pediatrics and epidemiology and population health at Stanford University in Stanford, California, told Medscape Medical News. “But this virus is ubiquitous. It’s found everywhere. It comes around every winter season. And immunity is not long-lasting.”

Older children who are not receiving monoclonal antibodies still experience RSV-related hospitalizations, suggesting the virus continues to circulate at high enough levels in the community. “The vaccine and monoclonal antibodies can reduce the risk of hospitalization and more severe disease in young kids, but they won’t eliminate the virus,” Maldonado said. “Right now, the goal is to prevent serious infection, not to prevent the spread of the virus completely.”

Expanding Access to RSV Prevention in Low-Income Countries

Currently, the RSV vaccine and monoclonal antibodies are only given in the United States, Europe, United Kingdom, and Canada to newborns, children at risk for severe disease, and pregnant women. However, Midulla said that pharmaceutical companies are pushing to broaden the rollout to a broader population within these countries. Yet, he said, over 99% of RSV infection–related deaths occur in the Global South.

No pharmaceutical company has sought approval in low-income countries such as those in Africa. “Unless they see there being a market in a country, they’re not going to go through the onerous process of getting [a vaccine] licensed,” Shabir Madhi, dean of the faculty of health sciences and a professor of vaccinology at the University of the Witwatersrand, Johannesburg, South Africa, told Medscape Medical News.

He highlighted that almost 50% of RSV-related deaths occur in African children younger than 5 years, despite these children comprising just one fifth of the global under-5 population. The high burden of RSV mortality in the Global South is mainly due to poor access to healthcare and supportive treatments, such as supplemental oxygen, which can help children recover from severe RSV infection.

Companies are unlikely to pursue regulatory approval and licensing in low- and middle-income countries until GAVI, the global vaccine alliance, commits to procuring and funding the vaccines for these regions. GAVI’s decision would provide the necessary market incentive for manufacturers to seek approval.

Madhi suggested that GAVI’s decision on RSV vaccine procurement is imminent, likely early next year, following the World Health Organization’s Strategic Advisory Group of Experts on Immunization recommendation to vaccinate all pregnant women with the RSV vaccine, regardless of whether they are in high-income or low-income countries.

Nevertheless, even if vaccines become available, many African countries may still struggle to afford them. Madhi said that these countries would likely depend on GAVI and organizations like UNICEF to procure the vaccines at affordable prices. “The unfortunate reality is that many countries — especially in Africa — still wouldn’t be able to afford it, even if the vaccine cost as little as $5,” said Madhi. “But that’s where they would have the greatest impact.”

Midulla, Pijnenburg reported no relevant financial relationships. Madhi’s research unit, the Vaccines and Infectious Disease Analytics Unit, was involved in the clinical trials for the Pfizer RSV vaccine, the GSK RSV vaccine (which was terminated), as well as the MEDLEY trial of palivizumab. All funding for these studies went to his institution, the University of the Witwatersrand. Maldonado was Stanford principal investigator for the Pfizer RSV vaccine.
 

A version of this article appeared on Medscape.com.

Almost 70 years after the discovery of the respiratory syncytial virus (RSV), vaccines and preventive treatments are giving babies a chance to beat the potentially deadly childhood infection.

As doctors turn to monoclonal antibody therapies and governments plan vaccination programs, clinical researchers are asking whether these measures will reduce the spread of the virus. Will fewer babies die from RSV, and fewer children develop permanent wheezing?

Recent studies offer clues.

Fabio Midulla, an associate professor of pediatrics at Sapienza University of Rome in Rome, Italy, said that the pharmaceutical industry is poised to push governments to use vaccines and monoclonal antibodies for even more children. “Such a push might work,” he said at the European Respiratory Society (ERS) 2024 Congress, “given that several studies have already demonstrated that their use can improve outcomes for children who do become infected and reduce societal costs by reducing hospitalizations.”

But Mariëlle WH Pijnenburg, a pulmonary specialist at Erasmus University Rotterdam in the Netherlands, said at the Congress that greater rollout would require governments to force industry to lower prices. If treatments remain beyond the reach of lower-income countries — where the burden of RSV is the greatest — the death toll from this common childhood infection will remain stubbornly high, and the prospect of global elimination will remain forever out of reach, she said.

New Tools in the Fight Against RSV

Nirsevimab, a long-acting monoclonal antibody given to newborns to prevent severe infection, was approved by the European Medicines Agency (EMA) in October 2022 and the US Food and Drug Administration (FDA) in July 2023. And Abrysvo, a vaccine given to older adults and pregnant women to stop them from passing the virus to babies from birth through 6 months of age, was approved by the FDA and the EMA in 2023.

RSV is responsible for over 33 million lung infections in children younger than 5 years annually, with more than 4 million hospitalizations and nearly 200,000 deaths. According to the Centers for Disease Control and Prevention, every year, 2.1 million children younger than 5 years old visit a healthcare provider because of an RSV infection and between 58,000 and 80,000 children younger than 5 years old are hospitalized in the United States. The burden of severe RSV disease is also high among adults, with an estimated 123,000-193,000 hospitalizations, 24,400-34,900 ICU admissions, and 4680-8620 in-hospital deaths occurring annually among US adults.

While the virus affects all age groups, it is particularly severe in infants, swelling their airways and causing them to struggle for breath. Infection in infancy can lead to later complications, such as the development of wheezing, a condition that causes breathlessness and a feeling of tightening in the chest, and possibly also asthma.

Studies have shown that children and preterm infants infected with RSV who were given monoclonal antibodies experienced less post-infection wheezing, suggesting that RSV prophylaxis could prevent the development of wheezing bronchitis.

A study conducted in Galicia, Spain, showed that only 0.3% of infants who received prophylaxis with Nirsevimab were hospitalized for RSV-related lower respiratory tract infections. “This is very promising,” Yvonne Maldonado, MD, professor of pediatrics and epidemiology and population health at Stanford University in Stanford, California, told Medscape Medical News. “But this virus is ubiquitous. It’s found everywhere. It comes around every winter season. And immunity is not long-lasting.”

Older children who are not receiving monoclonal antibodies still experience RSV-related hospitalizations, suggesting the virus continues to circulate at high enough levels in the community. “The vaccine and monoclonal antibodies can reduce the risk of hospitalization and more severe disease in young kids, but they won’t eliminate the virus,” Maldonado said. “Right now, the goal is to prevent serious infection, not to prevent the spread of the virus completely.”

Expanding Access to RSV Prevention in Low-Income Countries

Currently, the RSV vaccine and monoclonal antibodies are only given in the United States, Europe, United Kingdom, and Canada to newborns, children at risk for severe disease, and pregnant women. However, Midulla said that pharmaceutical companies are pushing to broaden the rollout to a broader population within these countries. Yet, he said, over 99% of RSV infection–related deaths occur in the Global South.

No pharmaceutical company has sought approval in low-income countries such as those in Africa. “Unless they see there being a market in a country, they’re not going to go through the onerous process of getting [a vaccine] licensed,” Shabir Madhi, dean of the faculty of health sciences and a professor of vaccinology at the University of the Witwatersrand, Johannesburg, South Africa, told Medscape Medical News.

He highlighted that almost 50% of RSV-related deaths occur in African children younger than 5 years, despite these children comprising just one fifth of the global under-5 population. The high burden of RSV mortality in the Global South is mainly due to poor access to healthcare and supportive treatments, such as supplemental oxygen, which can help children recover from severe RSV infection.

Companies are unlikely to pursue regulatory approval and licensing in low- and middle-income countries until GAVI, the global vaccine alliance, commits to procuring and funding the vaccines for these regions. GAVI’s decision would provide the necessary market incentive for manufacturers to seek approval.

Madhi suggested that GAVI’s decision on RSV vaccine procurement is imminent, likely early next year, following the World Health Organization’s Strategic Advisory Group of Experts on Immunization recommendation to vaccinate all pregnant women with the RSV vaccine, regardless of whether they are in high-income or low-income countries.

Nevertheless, even if vaccines become available, many African countries may still struggle to afford them. Madhi said that these countries would likely depend on GAVI and organizations like UNICEF to procure the vaccines at affordable prices. “The unfortunate reality is that many countries — especially in Africa — still wouldn’t be able to afford it, even if the vaccine cost as little as $5,” said Madhi. “But that’s where they would have the greatest impact.”

Midulla, Pijnenburg reported no relevant financial relationships. Madhi’s research unit, the Vaccines and Infectious Disease Analytics Unit, was involved in the clinical trials for the Pfizer RSV vaccine, the GSK RSV vaccine (which was terminated), as well as the MEDLEY trial of palivizumab. All funding for these studies went to his institution, the University of the Witwatersrand. Maldonado was Stanford principal investigator for the Pfizer RSV vaccine.
 

A version of this article appeared on Medscape.com.

TOPLINE:

Hypermucoviscous Klebsiella pneumoniae (hmKp) strains demonstrate a significantly lower prevalence of extended-spectrum beta-lactamase (ESBL) production and slightly lower carbapenem resistance than non-hmKp strains, according to a recent meta-analysis of 2049 clinical isolates.

METHODOLOGY:

• Researchers conducted a meta-analysis to assess the prevalence of ESBL-producing strains and carbapenem-resistant strains among the hmKp and non-hmKp clinical isolates.
• They included 15 studies published between 2014 and 2023, with 2049 clinical isolates of K pneumoniae identified using a string test to distinguish hypermucoviscous from non-hypermucoviscous strains.
• These studies spanned across four continents: Asia, Africa, Europe, and North America.
• The primary outcome was the prevalence of ESBL-producing and carbapenem-resistant strains, determined through antimicrobial susceptibility testing.

TAKEAWAY:

• The hmKp strains were associated with a significantly lower prevalence of ESBL-producing strains than non-hmKp strains (pooled odds ratio [OR], 0.26; P = .003).
• Similarly, hmKp strains were associated with a slightly lower prevalence of carbapenem-resistant strains than non-hmKp strains (pooled OR, 0.63; P = .038).

IN PRACTICE:

“Therapeutic options for CRKP [carbapenem-resistant K pneumoniae] infections are extremely limited due to the scarcity of effective antibacterial drugs. Therefore, it is crucial to consider the risks posed by CRKP strains when administering treatment to patients with hmKp infections and a history of the aforementioned risk factors,” the authors wrote.

SOURCE:

The study was led by Hiroki Namikawa, Department of Medical Education and General Practice, Graduate School of Medicine, Osaka Metropolitan University, Japan. It was published online on December 16, 2024, in Emerging Microbes & Infections.

LIMITATIONS:

Only three databases (PubMed, Scopus, and Cochrane Library) were searched for identifying studies, potentially missing relevant studies from other sources. Furthermore, only articles published in English were included, which may have restricted the scope of analysis. Additionally, geographical distribution was predominantly limited to Asia, limiting the global applicability of the results.

DISCLOSURES:

No funding sources were mentioned, and no conflicts of interest were reported.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.

TOPLINE:

Hypermucoviscous Klebsiella pneumoniae (hmKp) strains demonstrate a significantly lower prevalence of extended-spectrum beta-lactamase (ESBL) production and slightly lower carbapenem resistance than non-hmKp strains, according to a recent meta-analysis of 2049 clinical isolates.

METHODOLOGY:

• Researchers conducted a meta-analysis to assess the prevalence of ESBL-producing strains and carbapenem-resistant strains among the hmKp and non-hmKp clinical isolates.
• They included 15 studies published between 2014 and 2023, with 2049 clinical isolates of K pneumoniae identified using a string test to distinguish hypermucoviscous from non-hypermucoviscous strains.
• These studies spanned across four continents: Asia, Africa, Europe, and North America.
• The primary outcome was the prevalence of ESBL-producing and carbapenem-resistant strains, determined through antimicrobial susceptibility testing.

TAKEAWAY:

• The hmKp strains were associated with a significantly lower prevalence of ESBL-producing strains than non-hmKp strains (pooled odds ratio [OR], 0.26; P = .003).
• Similarly, hmKp strains were associated with a slightly lower prevalence of carbapenem-resistant strains than non-hmKp strains (pooled OR, 0.63; P = .038).

IN PRACTICE:

“Therapeutic options for CRKP [carbapenem-resistant K pneumoniae] infections are extremely limited due to the scarcity of effective antibacterial drugs. Therefore, it is crucial to consider the risks posed by CRKP strains when administering treatment to patients with hmKp infections and a history of the aforementioned risk factors,” the authors wrote.

SOURCE:

The study was led by Hiroki Namikawa, Department of Medical Education and General Practice, Graduate School of Medicine, Osaka Metropolitan University, Japan. It was published online on December 16, 2024, in Emerging Microbes & Infections.

LIMITATIONS:

Only three databases (PubMed, Scopus, and Cochrane Library) were searched for identifying studies, potentially missing relevant studies from other sources. Furthermore, only articles published in English were included, which may have restricted the scope of analysis. Additionally, geographical distribution was predominantly limited to Asia, limiting the global applicability of the results.

DISCLOSURES:

No funding sources were mentioned, and no conflicts of interest were reported.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.

TOPLINE:

Hypermucoviscous Klebsiella pneumoniae (hmKp) strains demonstrate a significantly lower prevalence of extended-spectrum beta-lactamase (ESBL) production and slightly lower carbapenem resistance than non-hmKp strains, according to a recent meta-analysis of 2049 clinical isolates.

METHODOLOGY:

• Researchers conducted a meta-analysis to assess the prevalence of ESBL-producing strains and carbapenem-resistant strains among the hmKp and non-hmKp clinical isolates.
• They included 15 studies published between 2014 and 2023, with 2049 clinical isolates of K pneumoniae identified using a string test to distinguish hypermucoviscous from non-hypermucoviscous strains.
• These studies spanned across four continents: Asia, Africa, Europe, and North America.
• The primary outcome was the prevalence of ESBL-producing and carbapenem-resistant strains, determined through antimicrobial susceptibility testing.

TAKEAWAY:

• The hmKp strains were associated with a significantly lower prevalence of ESBL-producing strains than non-hmKp strains (pooled odds ratio [OR], 0.26; P = .003).
• Similarly, hmKp strains were associated with a slightly lower prevalence of carbapenem-resistant strains than non-hmKp strains (pooled OR, 0.63; P = .038).

IN PRACTICE:

“Therapeutic options for CRKP [carbapenem-resistant K pneumoniae] infections are extremely limited due to the scarcity of effective antibacterial drugs. Therefore, it is crucial to consider the risks posed by CRKP strains when administering treatment to patients with hmKp infections and a history of the aforementioned risk factors,” the authors wrote.

SOURCE:

The study was led by Hiroki Namikawa, Department of Medical Education and General Practice, Graduate School of Medicine, Osaka Metropolitan University, Japan. It was published online on December 16, 2024, in Emerging Microbes & Infections.

LIMITATIONS:

Only three databases (PubMed, Scopus, and Cochrane Library) were searched for identifying studies, potentially missing relevant studies from other sources. Furthermore, only articles published in English were included, which may have restricted the scope of analysis. Additionally, geographical distribution was predominantly limited to Asia, limiting the global applicability of the results.

DISCLOSURES:

No funding sources were mentioned, and no conflicts of interest were reported.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.

The first human patient in the United States with a confirmed case of avian influenza has died, according to a press release from the Louisiana Department of Health. The individual was older than 65 years and had underlying medical conditions and remains the only known human case in the state.

The patient contracted highly pathogenic avian influenza, also known as H5N1, through exposure to wild birds and a noncommercial backyard flock, according to the release. The Louisiana Department of Health has found no additional H5H1 cases in the state and no evidence of person-to-person transmission.

The Centers for Disease Control and Prevention (CDC) conducted genetic sequencing of specimens of the virus collected from the Louisiana patient. The agency compared the sequences with sequences from dairy cows, wild birds, and poultry in various areas of the United States that were infected with the H5N1 virus.

The Louisiana patient was infected with the D1.1 genotype of the H5N1 virus. Although D1.1 is related to other D1.1 viruses found in recent human cases in Washington State and British Columbia, Canada, it is distinct from the widely spreading B3.13 genotype that has caused H5N1 outbreaks in dairy cows, poultry, and other animals and has been linked to sporadic human cases in the United States, according to the CDC.

Despite evidence of some changes in the virus between the Louisiana patient and samples from poultry on the patient’s property, “these changes would be more concerning if found in animal hosts or in early stages of infection,” according to the CDC. The CDC and the Louisiana Department of Health are conducting additional sequencing to facilitate further analysis.

In the meantime, the risk to the general public for H5N1 remains low, but individuals who work with or have recreational exposure to birds, poultry, or cows remain at increased risk.

The CDC and the Louisiana Department of Health advise individuals to reduce the risk for H5N1 exposure by avoiding direct contact with wild birds or other animals infected or possibly infected with the virus, avoiding any contact with dead animals, and keeping pets away from sick or dead animals and their feces. Additional safety measures include avoiding uncooked food products such as unpasteurized raw milk or cheese from animals with suspected or confirmed infections and reporting sick or dead birds or animals to the US Department of Agriculture by calling 1-866-536-7593 or the Louisiana Department of Agriculture and Forestry Diagnostic Lab by calling 318-927-3441.

The CDC advises clinicians to consider H5N1 in patients presenting with conjunctivitis or signs of acute respiratory illness and a history of high-risk exposure, including handling sick or dead animals, notably birds and livestock, within 10 days before the onset of symptoms. Other risk factors include consuming uncooked or undercooked food, direct contact with areas contaminated with feces, direct contact with unpasteurized milk or other dairy products or with parts of potentially infected animals, and prolonged exposure to infected animals in a confined space.

Clinical symptoms also may include gastrointestinal complaints such as diarrhea, as well as fatigue, arthralgia, and headache. Patients with more severe H5N1 may experience shortness of breath, altered mental state, and seizures, and serious complications of the virus include pneumonia, acute respiratory distress syndrome, multiorgan failure, and sepsis, according to the CDC.

Clinicians who suspect H5N1 cases should contact their local public health departments. The CDC offers additional advice on evaluating and managing patients with novel influenza A viruses.

 

A Clinician’s Take

“Some symptoms of avian flu include fever, cough, sore throat, runny nose, fatigue, body aches or eye redness or irritation,” Shirin A. Mazumder, MD, associate professor and infectious disease specialist at The University of Tennessee Health Science Center, Memphis, said in an interview. “The timing to the development of symptoms after exposure is typically within 10 days. Avian influenza should be considered when individuals develop symptoms with a relevant exposure history,” she said. 

Whenever possible, avoidance of sick or dead birds and other animals is ideal, but for those who must have contact with sick or dead birds, poultry, or other animals, personal protective equipment (PPE) including a respirator, goggles, and disposable gloves is recommended, said Mazumder. 

“For those working in high-exposure settings, additional PPE including boots or boot covers, hair cover, and fluid-resistant coveralls are recommended,” she said. “Other protective measures include avoiding touching surfaces or materials contaminated with feces, mucus, and saliva from infected animals and avoid[ing] the consumption of raw milk, raw milk products, and undercooked meat from infected animals,” she added.

Hunters handling wild game should dress birds in the field, practice good hand hygiene, and use a respirator or well-fitting mask and gloves when handling the animals to help prevent disease, said Mazumder. 

In addition, those working with confirmed or suspected H5N1 cases should monitor themselves for symptoms, said Mazumder. “Those who become ill within 10 days of exposure to an infected animal or source should isolate from household members and avoid going to work or school until infection is excluded. It is important to reach out to a healthcare professional if you think you may have been exposed or if you think you are infected,” she said. 

There is no currently available vaccine for H5N1 infection, but oseltamivir can be used for chemoprophylaxis and treatment, said Mazumder. “The seasonal flu vaccine does not protect against avian influenza; however, it is still important to ensure that you are up to date on the latest flu vaccine to prevent the possibility of a coinfection with seasonal flu and avian flu,” she emphasized. 

More research is needed to better understand how the influenza virus is transmitted, said Mazumder. “The potential for the virus to evolve and mutate, and how it affects different hosts, are all factors that can impact public health decisions,” she said. “In addition, further research into finding a vaccine and improving surveillance methods are necessary for disease prevention,” she said. 

Mazumder had no financial conflicts to disclose. 
 

A version of this article appeared on Medscape.com.

The first human patient in the United States with a confirmed case of avian influenza has died, according to a press release from the Louisiana Department of Health. The individual was older than 65 years and had underlying medical conditions and remains the only known human case in the state.

The patient contracted highly pathogenic avian influenza, also known as H5N1, through exposure to wild birds and a noncommercial backyard flock, according to the release. The Louisiana Department of Health has found no additional H5H1 cases in the state and no evidence of person-to-person transmission.

The Centers for Disease Control and Prevention (CDC) conducted genetic sequencing of specimens of the virus collected from the Louisiana patient. The agency compared the sequences with sequences from dairy cows, wild birds, and poultry in various areas of the United States that were infected with the H5N1 virus.

The Louisiana patient was infected with the D1.1 genotype of the H5N1 virus. Although D1.1 is related to other D1.1 viruses found in recent human cases in Washington State and British Columbia, Canada, it is distinct from the widely spreading B3.13 genotype that has caused H5N1 outbreaks in dairy cows, poultry, and other animals and has been linked to sporadic human cases in the United States, according to the CDC.

Despite evidence of some changes in the virus between the Louisiana patient and samples from poultry on the patient’s property, “these changes would be more concerning if found in animal hosts or in early stages of infection,” according to the CDC. The CDC and the Louisiana Department of Health are conducting additional sequencing to facilitate further analysis.

In the meantime, the risk to the general public for H5N1 remains low, but individuals who work with or have recreational exposure to birds, poultry, or cows remain at increased risk.

The CDC and the Louisiana Department of Health advise individuals to reduce the risk for H5N1 exposure by avoiding direct contact with wild birds or other animals infected or possibly infected with the virus, avoiding any contact with dead animals, and keeping pets away from sick or dead animals and their feces. Additional safety measures include avoiding uncooked food products such as unpasteurized raw milk or cheese from animals with suspected or confirmed infections and reporting sick or dead birds or animals to the US Department of Agriculture by calling 1-866-536-7593 or the Louisiana Department of Agriculture and Forestry Diagnostic Lab by calling 318-927-3441.

The CDC advises clinicians to consider H5N1 in patients presenting with conjunctivitis or signs of acute respiratory illness and a history of high-risk exposure, including handling sick or dead animals, notably birds and livestock, within 10 days before the onset of symptoms. Other risk factors include consuming uncooked or undercooked food, direct contact with areas contaminated with feces, direct contact with unpasteurized milk or other dairy products or with parts of potentially infected animals, and prolonged exposure to infected animals in a confined space.

Clinical symptoms also may include gastrointestinal complaints such as diarrhea, as well as fatigue, arthralgia, and headache. Patients with more severe H5N1 may experience shortness of breath, altered mental state, and seizures, and serious complications of the virus include pneumonia, acute respiratory distress syndrome, multiorgan failure, and sepsis, according to the CDC.

Clinicians who suspect H5N1 cases should contact their local public health departments. The CDC offers additional advice on evaluating and managing patients with novel influenza A viruses.

 

A Clinician’s Take

“Some symptoms of avian flu include fever, cough, sore throat, runny nose, fatigue, body aches or eye redness or irritation,” Shirin A. Mazumder, MD, associate professor and infectious disease specialist at The University of Tennessee Health Science Center, Memphis, said in an interview. “The timing to the development of symptoms after exposure is typically within 10 days. Avian influenza should be considered when individuals develop symptoms with a relevant exposure history,” she said. 

Whenever possible, avoidance of sick or dead birds and other animals is ideal, but for those who must have contact with sick or dead birds, poultry, or other animals, personal protective equipment (PPE) including a respirator, goggles, and disposable gloves is recommended, said Mazumder. 

“For those working in high-exposure settings, additional PPE including boots or boot covers, hair cover, and fluid-resistant coveralls are recommended,” she said. “Other protective measures include avoiding touching surfaces or materials contaminated with feces, mucus, and saliva from infected animals and avoid[ing] the consumption of raw milk, raw milk products, and undercooked meat from infected animals,” she added.

Hunters handling wild game should dress birds in the field, practice good hand hygiene, and use a respirator or well-fitting mask and gloves when handling the animals to help prevent disease, said Mazumder. 

In addition, those working with confirmed or suspected H5N1 cases should monitor themselves for symptoms, said Mazumder. “Those who become ill within 10 days of exposure to an infected animal or source should isolate from household members and avoid going to work or school until infection is excluded. It is important to reach out to a healthcare professional if you think you may have been exposed or if you think you are infected,” she said. 

There is no currently available vaccine for H5N1 infection, but oseltamivir can be used for chemoprophylaxis and treatment, said Mazumder. “The seasonal flu vaccine does not protect against avian influenza; however, it is still important to ensure that you are up to date on the latest flu vaccine to prevent the possibility of a coinfection with seasonal flu and avian flu,” she emphasized. 

More research is needed to better understand how the influenza virus is transmitted, said Mazumder. “The potential for the virus to evolve and mutate, and how it affects different hosts, are all factors that can impact public health decisions,” she said. “In addition, further research into finding a vaccine and improving surveillance methods are necessary for disease prevention,” she said. 

Mazumder had no financial conflicts to disclose. 
 

A version of this article appeared on Medscape.com.

The first human patient in the United States with a confirmed case of avian influenza has died, according to a press release from the Louisiana Department of Health. The individual was older than 65 years and had underlying medical conditions and remains the only known human case in the state.

The patient contracted highly pathogenic avian influenza, also known as H5N1, through exposure to wild birds and a noncommercial backyard flock, according to the release. The Louisiana Department of Health has found no additional H5H1 cases in the state and no evidence of person-to-person transmission.

The Centers for Disease Control and Prevention (CDC) conducted genetic sequencing of specimens of the virus collected from the Louisiana patient. The agency compared the sequences with sequences from dairy cows, wild birds, and poultry in various areas of the United States that were infected with the H5N1 virus.

The Louisiana patient was infected with the D1.1 genotype of the H5N1 virus. Although D1.1 is related to other D1.1 viruses found in recent human cases in Washington State and British Columbia, Canada, it is distinct from the widely spreading B3.13 genotype that has caused H5N1 outbreaks in dairy cows, poultry, and other animals and has been linked to sporadic human cases in the United States, according to the CDC.

Despite evidence of some changes in the virus between the Louisiana patient and samples from poultry on the patient’s property, “these changes would be more concerning if found in animal hosts or in early stages of infection,” according to the CDC. The CDC and the Louisiana Department of Health are conducting additional sequencing to facilitate further analysis.

In the meantime, the risk to the general public for H5N1 remains low, but individuals who work with or have recreational exposure to birds, poultry, or cows remain at increased risk.

The CDC and the Louisiana Department of Health advise individuals to reduce the risk for H5N1 exposure by avoiding direct contact with wild birds or other animals infected or possibly infected with the virus, avoiding any contact with dead animals, and keeping pets away from sick or dead animals and their feces. Additional safety measures include avoiding uncooked food products such as unpasteurized raw milk or cheese from animals with suspected or confirmed infections and reporting sick or dead birds or animals to the US Department of Agriculture by calling 1-866-536-7593 or the Louisiana Department of Agriculture and Forestry Diagnostic Lab by calling 318-927-3441.

The CDC advises clinicians to consider H5N1 in patients presenting with conjunctivitis or signs of acute respiratory illness and a history of high-risk exposure, including handling sick or dead animals, notably birds and livestock, within 10 days before the onset of symptoms. Other risk factors include consuming uncooked or undercooked food, direct contact with areas contaminated with feces, direct contact with unpasteurized milk or other dairy products or with parts of potentially infected animals, and prolonged exposure to infected animals in a confined space.

Clinical symptoms also may include gastrointestinal complaints such as diarrhea, as well as fatigue, arthralgia, and headache. Patients with more severe H5N1 may experience shortness of breath, altered mental state, and seizures, and serious complications of the virus include pneumonia, acute respiratory distress syndrome, multiorgan failure, and sepsis, according to the CDC.

Clinicians who suspect H5N1 cases should contact their local public health departments. The CDC offers additional advice on evaluating and managing patients with novel influenza A viruses.

 

A Clinician’s Take

“Some symptoms of avian flu include fever, cough, sore throat, runny nose, fatigue, body aches or eye redness or irritation,” Shirin A. Mazumder, MD, associate professor and infectious disease specialist at The University of Tennessee Health Science Center, Memphis, said in an interview. “The timing to the development of symptoms after exposure is typically within 10 days. Avian influenza should be considered when individuals develop symptoms with a relevant exposure history,” she said. 

Whenever possible, avoidance of sick or dead birds and other animals is ideal, but for those who must have contact with sick or dead birds, poultry, or other animals, personal protective equipment (PPE) including a respirator, goggles, and disposable gloves is recommended, said Mazumder. 

“For those working in high-exposure settings, additional PPE including boots or boot covers, hair cover, and fluid-resistant coveralls are recommended,” she said. “Other protective measures include avoiding touching surfaces or materials contaminated with feces, mucus, and saliva from infected animals and avoid[ing] the consumption of raw milk, raw milk products, and undercooked meat from infected animals,” she added.

Hunters handling wild game should dress birds in the field, practice good hand hygiene, and use a respirator or well-fitting mask and gloves when handling the animals to help prevent disease, said Mazumder. 

In addition, those working with confirmed or suspected H5N1 cases should monitor themselves for symptoms, said Mazumder. “Those who become ill within 10 days of exposure to an infected animal or source should isolate from household members and avoid going to work or school until infection is excluded. It is important to reach out to a healthcare professional if you think you may have been exposed or if you think you are infected,” she said. 

There is no currently available vaccine for H5N1 infection, but oseltamivir can be used for chemoprophylaxis and treatment, said Mazumder. “The seasonal flu vaccine does not protect against avian influenza; however, it is still important to ensure that you are up to date on the latest flu vaccine to prevent the possibility of a coinfection with seasonal flu and avian flu,” she emphasized. 

More research is needed to better understand how the influenza virus is transmitted, said Mazumder. “The potential for the virus to evolve and mutate, and how it affects different hosts, are all factors that can impact public health decisions,” she said. “In addition, further research into finding a vaccine and improving surveillance methods are necessary for disease prevention,” she said. 

Mazumder had no financial conflicts to disclose. 
 

A version of this article appeared on Medscape.com.