Avian Influenza

Avian influenza is a common viral disease of birds that can infect humans and other mammals. The viruses are classified as having low pathogenicity or high pathogenicity based on the severity of the illness they cause in poultry and most are not considered a public health threat. The virus is shed through all excretions (saliva, feces) and is highly contagious among birds.

Highly pathogenic avian influenza (HPAI) outbreaks are suspected when a large number of sick or dead birds is encountered at the same place and time. Traditionally, the virus has most significantly impacted waterfowl and shorebirds (ducks, geese), wild poultry (turkey, grouse), raptors (hawks, eagles), and other avian scavengers (crows, gulls, ravens). Live infected birds can exhibit neurologic signs, such as swimming/walking in circles, holding their heads/necks in an unnatural position, an inability to smoothly rotate/tilt their heads, tremoring, seizing, and having difficulty flying. However, neurologic signs in birds can result from other causes including trauma, exposure to toxins, as well as infection from bacteria, fungi, or non-influenza viruses.

Avian influenza can be spread by legal and illegal movement of infected birds, poultry products, contaminated materials, equipment and vehicles, as well as via wild bird migration.

Migratory birds – typically waterfowl, shorebirds, gulls, and terns – are natural carriers of avian influenza and are considered the natural reservoir for low-pathogenic strains of the disease. The impact of highly pathogenic avian influenza (HPAI) on migratory birds and the role that wild birds play in the spread is unclear but the focus of ongoing research. Once infected with HPAI, wild birds can transport the virus to a new location, but infected birds are rarely able to travel far and often quickly die.

Hunters should follow routine precautions when hunting and handling birds:

• Do not harvest or handle wild birds that appear sick or are found dead.
• Do not eat, drink, or smoke while handling birds.
• Wear washable or disposable gloves while handling and cleaning birds.
• Wash hands and any tools or work surfaces that come in contact with birds with soap and water. An alcohol-based sanitizer can be used if soap and water is not available. Following cleaning, tools and work surfaces can be disinfected with a 10% household bleach solution; to ensure adequate disinfection, allow to air dry or rinse with clean water after 10 minutes of contact time.
• Cook all wild bird meat to 160°F.

Avian influenza typically does not affect bird species that frequent backyard bird feeders. However, one should always exercise good hygiene when maintaining bird feeders and baths to prevent the spread of disease. Every couple of weeks, feeders and baths should be emptied, washed with soapy water, rinsed, then a 10% household bleach solution should be applied to disinfect them before refilling (either allow a 10-minute contact time before rinsing or allow to air dry). Any spilled seed should also be cleaned up to mitigate disease spread. If you notice multiple sick or dead birds over a short period of time, you should strongly consider leaving feeders down and baths empty to not make any potential outbreak worse.

A certain level of sickness (morbidity) or death (mortality) is expected in wild birds and can occur for a variety of reasons. Pennsylvanians can assist with HPAI surveillance efforts by reporting any sick or dead wild birds, particularly wild poultry (turkey, grouse), raptors (hawks, eagles), avian scavengers (crows, gulls, ravens), and waterfowl species (ducks, geese), to the Game Commission at 833-PGC-WILD. The Game Commission does not advise that the public handle any abnormal, injured, sick or dead wildlife unless authorized to do so. However, if you have a dead wild bird on your property and haven’t heard back from the Game Commission within 24 hours, you may wish to dispose of the carcass. Disposal via burial or commercial/residential trash is appropriate and will protect scavenging wildlife. If electing to dispose of the carcass, the following guidance is provided:

1. Before picking up the wild bird carcass, put on either disposable or washable gloves. If gloves are unavailable, a plastic bag can be used as a makeshift glove.
2. If performing on-site burial, a burial hole at least 2 feet deep will discourage scavenging. Do not bury the carcass in an area that could contaminate a water supply.
3. If disposing of the carcass in commercial/residential trash, place the carcass in a plastic bag along with any disposal gloves that were used, then place everything in a second plastic bag before disposal.
4. Once disposal is complete, immediately wash your hands and any non-disposable gloves that were used.

Any sick or dead domestic birds should be reported to Pennsylvania Department of Agriculture at 717-772-2852.