Bird Flu (Avian Influenza)

Page originally published 5/1/2024. Last updated 6/9/2026.

Bird flu, also known as avian influenza A (H5N1) or highly pathogenic avian influenza (HPAI), is a disease caused by a viral infection. These viruses naturally spread among water birds, like ducks and geese. They can also spread to domestic poultry, like chickens and turkeys, in addition to wild and domestic mammals (such as cattle and cats). Although human infections with bird flu are rare, cases can occur among those with exposure to the virus. 

While the current risk to the public remains low, the County of San Diego is monitoring the situation and working to protect the public’s health.

Call the Epidemiology Unit at (619) 692-8499, or send an email, for more information.