Avian influenza (AI) viruses occur naturally among wild aquatic birds worldwide and can infect domestic poultry and other bird and animal species. Wild aquatic birds can be infected with avian influenza A viruses in their intestines and respiratory tract, but usually do not get sick.  

AI viruses are classified as either low pathogenic avian influenza (LPAI), or high pathogenic avian influenza (HPAI) according to the virus strain’s impact on domestic poultry. 

Clinical signs for viruses are markedly different from LP to HP AI viruses.

LPAI viruses cause mild respiratory signs such as sneezing, coughing, ocular and nasal discharge and occasionally swollen infraorbital sinuses in poultry. 
Sinusitis is common in domestic ducks, quail and turkeys. In layers and breeders there is commonly decreased egg production and fertility.

HPAI viruses cause severe, systemic disease with high mortality in chickens, turkeys, and other gallinaceous poultry; mortality can be as high as 100% in a few days. 

AI is transmitted between individual birds by ingestion or inhalation and betweeen farms by breaches in biosecurity practices. Infected birds shed avian influenza virus in their saliva, mucous, and feces.

Both AI viruses can be isolated from choanal and cloacal swabs, and HPAI viruses from many internal organs.

There is no effective treatment for HPAI but depopulation can control the spread of the virus. 

Source: Cornell Wildlife Health Lab

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.

Low Risk of Avian Flu to Songbirds

There has been widespread transmission of avian flu to wild bird species including waterfowl and raptors. However, there have been relatively few documented cases of HPAI in songbirds and other typical feeder visitors to date, although this may change with increased testing or changes to the virus. That means there is currently a low risk of an outbreak among wild songbirds, and no official recommendation to take down feeders unless you also keep domestic poultry, according to the National Wildlife Disease Program. We do always recommend that you clean bird feeders and birdbaths regularly as a way to keep many kinds of diseases at bay. 

If songbirds are at low risk, why are people who keep poultry advised to take down their bird feeders?

The main concern with songbirds is the chance that a rare individual might transmit an infection to poultry. This is a concern because poultry are so much more vulnerable than songbirds to HPAI.

The key intervention is to keep songbirds away from poultry; it’s less important to keep songbirds away from each other.

If you have a backyard poultry flock, these are the most important steps to take:

make their food inaccessible to wild birds

make their water inaccessible to wild birds

keep poultry indoors or otherwise physically separated from wild birds, if possible

change your clothes and wash hands before tending to poultry (or pet birds)

As a secondary measure, USDA APHIS recommends for poultry owners to take down wild bird feeders or keep them well away from their captive flock

If you keep chickens or ducks, please see also latest information from the USDA Animal Plant and Health Inspection Service.  

Source: Cornell Lab of Ornithology

Owners of backyard flocks are encouraged to stay informed about where HPAI is occurring. In regions experiencing outbreaks, certain precautions can help stop the viruses from spreading:

Ensure areas where backyard birds are kept are fully enclosed, away from wild birds and their droppings.

Wash or sanitize your hands before and after handling birds, and when moving birds between coops.

Keep feed, drinking water, equipment, and other supplies secure, out of reach of wild birds or rodents.

Prevent visitors from contacting your flock, and avoid visits to places where other birds are kept.

Know the signs of HPAI, and immediately report any suspected infections to your veterinarian or New York State Department of Agriculture and Markets at (518) 457-3502 for poultry.

Call your veterinarian first, before bringing your bird(s) in to be seen.

Know the Signs of HPAI

Infected birds in backyard flocks, and possibly pet birds, may show one or more of the following signs:

Sudden death with no prior signs

Low energy or appetite

Purple discoloration or swelling of various body parts

Reduced egg production, or soft-shelled/misshapen eggs

Nasal discharge, coughing, or sneezing

Lack of coordination

Diarrhea

Immediately contact your veterinarian if you notice any of these signs so they can help you determine the best course of action.

Source: American Veterinary Medical Association

For additional safety precautions, please review our segment on wild bird feeders.