Cornell Lab, All About Birds
Originally published April 2022. Updated through February 2025 to reflect further developments in the outbreak.
Many people are concerned about the outbreak of avian influenza, or bird flu, that began in 2022 and has affected domestic poultry, waterfowl, raptors, shorebirds, other species of birds, and some mammals in many parts of the world. Because the current strain (H5N1) causes heavy losses to poultry, it is referred to as highly pathogenic avian influenza, or HPAI.
Transmission of avian influenza from birds to humans is rare, according to Centers for Disease Control’s summary of current avian influenza testing and infection statistics.
Reports of Avian Flu in Birds
This H5N1 strain of avian influenza virus affects a wide variety of wild birds, including hawks, eagles, falcons, owls, crows, vultures, shorebirds, game birds, seabirds, and especially waterfowl such as Canada Geese and Mallards (see list of species with HPAI detections, below). The virus is shed in the saliva, mucus, and feces of infected birds and is transmitted to other birds via ingestion or inhalation.
Because of the duration of this outbreak, its recent spread to mammal species, and widespread mortalities in some types of wild birds, there has been concern about whether it’s safe for people to feed wild birds. In January 2025, March 2023, and April 2022, we checked in with Dr. Sarah Bevins and Dr. Julianna Lenoch, who lead the USDA APHIS National Wildlife Disease Program to compile some key points regarding HPAI in songbirds and other feeder visitors…
Click here to read the whole article, and view the index of Wild bird species with HPAI detections in 2022–2025
Avian Influenza Outbreak: Should You Take Down Your Bird Feeders ?