The highly pathogenic avian influenza (HPAI) H5N1 virus, which is panzootic in poultry, can infect humans (1):
- since pandemic influenza virus has its origins in avian influenza viruses, HPAI H5N1 virus has to be considered a potentially serious pandemic threat
- infection with bird flu is widespread among wild birds and poultry (2)
- mammals such as dairy cows may also become infected
- bird flu can be transmitted to humans when viral particles from fluids and secretions of infected animals (saliva, mucus, faeces, milk) are inhaled or get into a person’s eyes, nose, or mouth
- multiple subtypes of bird flu have been linked to sporadic outbreaks of infections among humans, with the H5N1 and H7N9 subtypes the most common causes
Infection in humans
- symptoms of bird flu, which typically develop 2 to 7 days after exposure to the virus, are often similar to seasonal influenza and may include:
- fever
- cough
- sore throat
- coryza
- conjunctivitis
- myalgia
- headache
- fatigue
- complications of severe avian influenza include:
- pneumonia
- respiratory failure
- meningoencephalitis
Treatment with oseltamivir, twice daily for 5 days, is recommended for all patients with bird flu (2).
Reference:
- Peiris JS, de Jong MD, Guan Y. Avian influenza virus (H5N1): a threat to human health. Clin Microbiol Rev. 2007 Apr;20(2):243-67.
- Saravolatz LD, Malani PN. What Is Bird Flu? JAMA. Published online January 10, 2025.