What to know
- Presentation Day/Time: Wednesday, April 23, 9:00–10:25 am
- Presenter: Dennis Wang, MD, MPH, EIS officer assigned to the National Center for Immunization and Respiratory Diseases, Coronavirus and Other Respiratory Viruses Division
What did we do?
- During an outbreak of highly pathogenic avian influenza A(H5) in dairy cattle, officials in Tulare County, California identified multiple dairy farm workers with influenza A(H5) infection. From October-November 2024, we prospectively evaluated the durations of influenza A(H5) symptoms and viral RNA detection.
What did we find?
- Seven workers with presumptive influenza A(H5) had repeat testing; all were Hispanic males aged 18 years or older. All reported ocular, five reported constitutional, two reported respiratory, and one reported gastrointestinal symptoms.
- On initial influenza A(H5) testing conducted a median of two days after symptom onset, conjunctival swabs were positive for seven, nasal/oropharyngeal swabs for three, and nasopharyngeal swabs for none.
- All initiated oseltamivir a median of three days after symptom onset, and six initiated oseltamivir before re-testing; none were hospitalized.
- On the first repeat test, collected a median of five days after symptom onset, results were negative for six; one had a positive conjunctival swab three days after symptom onset, and a negative one two days later.
- Symptoms were reported for a median of 10 days; ocular and constitutional symptoms were reported for a median of six days.
Why does it matter?
- Viral detection duration was usually under a week, while symptom duration was longer among these antiviral-treated individuals. Additional data may inform recommendations around discontinuation of isolation prior to full clinical resolution, particularly for mild influenza A(H5) cases with ocular symptoms.
Abstract Category: Avian Flu