Avian Influenza

Sampling a wild bird for avaian influenza

Avian influenza, sometimes called bird flu, is an infectious disease caused by a group of influenza viruses that typically infect poultry and wild birds. In the winter of 2021-2022, a new highly pathogenic avian influenza (HPAI) virus, H5N1, was introduced into North America. Unlike previous HPAI viruses, this strain caused widespread mortality in some wild birds, particularly geese, raptors, cranes and vultures. It also affected several mammal species, particularly skunks, foxes and felids.

In 2022, this HPAI strain was detected in domestic poultry, wild birds and wild foxes in Minnesota. While the number of cases decreased in 2023, the virus continued to circulate among wild bird populations. In 2024, wild bird deaths from HPAI increased across the state once again. According to the Centers for Disease Control, this strain of avian influenza is considered to have a low risk to people. Risk of infection is mainly limited to people in direct contact with infected animals. More information on human cases and risks of avian influenza to people is available through the Minnesota Department of Health or the CDC.

  • Minnesota DNR, along with its partners, are continuing to monitor for HPAI in wild birds.
  • The DNR remains committed to helping inform the larger issue through collaboration with the Board of Animal Health and the Minnesota Department of Health.
  • The DNR will also continue to partner with USDA-Wildlife Services to participate in national surveillance programs as funding allows.
  • DNR is receiving and addressing sick and dead wildlife reports that are consistent with possible HPAI infections. Individuals can contact local DNR wildlife staff or the DNR information center at 888-646-6367 to report sick or dead birds. Reports of interest include:
    • Cases where five or more dead wild birds of any kind found in one location during the same timeframe.
    • Sick birds or mammals showing neurological signs or that die shortly after exhibiting these signs.
  • Wildlife suspected of potentially carrying HPAI will be tested or sent to the National Wildlife Health Center or Minnesota Veterinary Diagnostic Laboratory.
I’ve found a sick bird, what should I do?

Avoid handling the animal if possible. You can allow nature to take its course. While it is unfortunate, there are no available treatments for avian influenza. Raptors, in particular, decline quickly after contracting this illness.

Do not attempt to care for the animal yourself. While the risk of contracting this strain is low for people, there still is a risk. Wildlife rehabilitators are trained on how to limit contact and preserve a wild animal's natural instincts while giving care. Trained rehabilitators can assess the animal's condition and take necessary steps to care for the animal or humanely euthanize it if necessary.

You can find a list of local wildlife rehabilitators on DNR's website.

What can I do with dead birds I suspect died of avian influenza?

If you've found multiple dead birds (five or more of any species) in one place at one time, report the finding to the Minnesota DNR at 888-646-6367. DNR biologists may be interested in recording the possible case to track the virus.

If the biologists do not need the birds for sampling and you need to move them, wear disposable gloves, double bag the birds and place them in the trash.

Will avian influenza affect turkey hunting? Will I be at risk turkey hunting?

According to the Centers for Disease control (CDC), this strain of avian influenza is considered to have a low public health risk. While there have been multiple cases seen in humans, they are primarily associated with domestic animal contact. To date, all wild turkeys sampled by MNDNR tested negative for avian influenza; however, there have been cases reported in wild turkeys in other states. The USDA has guidelines for hunters if you wish to take precautions.

Should I take down my bird feeders?

National data on avian influenza in wild birds suggests that songbirds (passerines) have a low risk for avian influenza transmission. If you wish to take your feeders down as a precaution, you are encouraged to do so. Bird feeders only provide a supplemental source of food to birds, especially during the spring and summer.

Whether you choose to take your feeders down or leave them up, we do encourage you to clean your bird feeders regularly as this helps protect birds against other infections such as salmonella.

Is my dog or cat at risk of contracting avian influenza?

Few cases of this virus in dogs have been identified; however, there are several confirmed cases in domestic cats, especially those associated with affected poultry or cattle facilities. While the risk is low, there are precautions pet owners can take to protect their dogs and cats from avian influenza:

  • Avoid feeding pets raw meat from game birds or poultry.
  • Avoid feeding pets raw (unpasteurized) milk.
  • Keep pets away from wild birds that appear sick or are found dead of unknown causes.
  • Contact your veterinarian if your pet displays signs of illness.

For hunting dogs, we recommend not allowing dogs to retrieve or contact birds that appear sick. Hunters should avoid feeding their dogs raw meat from harvested birds during times when outbreaks are occurring. We also recommend keeping them away from field dressed carcasses or entrails.

I own chickens (or other fowl) - how can I protect my birds from getting avian influenza or potentially spreading it to wild birds?

Good biosecurity is essential for both commercial poultry facilities and backyard poultry owners to protect their birds from HPAI. Biosecurity is the way flocks are managed, and the various practices put in place to isolate flocks from outside sources of infection. The Board of Animal Health has biosecurity recommendations available for individuals who own backyard chickens and other fowl.

Signs & symptoms

Individual birds may exhibit the following signs of illness:

  • Inability to fly
  • Drooping head
  • Swimming in circles
  • Trouble standing upright
  • Tremors
  • Loss of coordination

Other signs of HPAI include multiple dead birds in the same location and timeframe.

Resources
About the virus

There are many strains of avian influenza viruses, and they are typically classified based on how they affect domestic chickens. This is called pathogenicity, which can be low or high.

  • Low pathogenic avian influenza viruses (LPAI) can infect domestic chickens, but usually do not cause severe illness.
  • Highly pathogenic avian influenza viruses (HPAI) can cause severe disease and mortality in domestic chickens. HPAI strains can kill entire flocks.

Wild waterfowl are natural hosts for many types of LPAI viruses and they usually don’t get sick from them. However, they can spread these viruses to domestic poultry and other wild birds. Occasionally, LPAI viruses can mutate or change to become highly pathogenic (HPAI).

Historically, detection of HPAI viruses in wild birds was rare and these viruses did not cause significant mortality or persist in North American wild birds.

H5N1 strain

In late 2021, a new strain of HPAI (H5N1) was introduced into North America. This virus has since been detected in numerous wild birds, domestic poultry, wild mammals, domestic cats and backyard flocks across the United States. Unlike prior strains of HPAI in North America, this strain did cause widespread mortality in some species of wild birds.

In spring 2024, HPAI cases began appearing in dairy cattle and then spread rapidly among cattle facilities in multiple states.

You can find more information on HPAI in cattle at the USDA website.

H5N2 strain

The 2015 HPAI, H5N2 virus strain that affected Minnesota was detected on the Pacific Coast in 2014 and did not have a significant impact on wild birds in Minnesota. The DNR and its partners conducted surveillance efforts in 2015 and only found one dead raptor that tested positive for the strain.

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