Bird Flu

Bird flu, avian influenza, is a type of flu in birds that can infect humans. Even though it happens rarely, bird flu symptoms can range from mild illness to serious and fatal conditions.


What is bird flu?

Bird flu, also called avian flu, is a strain of influenza (flu) that infects mostly wild water birds but can infect domestic birds (poultry) and other animals. These strains belong to influenza A type viruses.

It’s not usual, but bird flu can also infect people. The most common subtypes that may affect humans are A(H5N1), A(H7N9) and A(H9N2). The symptoms can range from mild (pink eye) to severe flu-like illness that results in respiratory failure or death.


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Who does bird flu affect?

Affected people include those who have generally had contact with live or dead infected birds. These can include domestic poultry (chickens, turkeys), waterfowl (ducks, geese) and birds of prey (falcons) that have been in contact with infected waterfowl in the wild. Infected birds shed the virus in their saliva, feces (poop) and mucus. In very rare cases, these people infected by contact with infected birds may have infected members of their families and other close contacts.

People who are most at risk of developing a serious illness after being infected by bird flu include:

  • Pregnant people.
  • People with poorly functioning immune systems.
  • People who are 65 years old or older.

Symptoms and Causes

What are the signs and symptoms of bird flu?

The signs and symptoms of bird flu in people may vary. They may include typical flu symptoms like:

Bird flu may also cause severe respiratory symptoms and conditions, including:

Infected individuals may also develop secondary bacterial infections. In severe cases of avian flu, an infected person might experience neurologic symptoms like seizures or mental changes. Bird flu might also cause multi-organ failure or septic shock.


What causes bird flu?

You can become infected if you breathe in the virus that is present in droplets or dust. You can also be infected by touching something infected and then touching your eyes, nose or mouth.

Bird flu has been passed from people who were infected to people who had no contact with infected birds, but this has been rare.

You can’t get bird flu from eating properly processed poultry or eats, but you should avoid eating anything that has raw poultry or blood as an ingredient.

Diagnosis and Tests

What tests will be done to diagnose bird flu?

Bird flu can’t be diagnosed by symptoms alone. Your provider may take a swab from your nose or throat. These specimens need to have specialized testing done and you may be referred to a public health department. Best results happen when the testing happens early, as symptoms develop.


Management and Treatment

How is bird flu treated?

Bird flu is treated with antiviral medications. Common treatments are:

  • Oseltamivir.
  • Peramivir.
  • Zanamivir.


How can I reduce my risk for bird flu?

The greatest risk is for people who work with poultry. If you have a job in the poultry industry, you should take precautions like wearing protective equipment at all times.

If you don’t work in the poultry industry, avoid poultry farms and markets if you’re traveling. Be careful if you are in contact with wild ducks or other waterfowl. Always practice good hand washing techniques and avoid touching your eyes, nose and mouth with unclean hands. If you do visit an area that has reports of bird flu, be sure to contact your healthcare provider immediately if you have any flu symptoms.

Poultry farmers and processors need to be aware of any type of bird flu in the area and to stop work immediately.

There’s a vaccine against bird flu in the U.S., but it’s not yet available to the public.

Outlook / Prognosis

What can I expect if I have this condition?

If you are diagnosed for bird flu and treated with appropriate antivirals, your outlook should be good.

Living With

How do I take care of myself if I have bird flu?

You can treat symptoms of bird flu the same way you would treat seasonal flu symptoms. This includes:

  • Taking any antiviral medication as prescribed.
  • Taking acetaminophen or ibuprofen as directed for symptoms like pain and fever.
  • Drinking plenty of fluids.
  • Getting plenty of rest.
  • Washing your hands often and taking care not to pass on any germs.

Additional Common Questions

How did bird flu start?

During the 1800s, people reported something called the "fowl plague" that was responsible for killing birds. Fowl plague was later found to be avian influenza or bird flu. Wild birds are unlikely to infect humans, but wild birds can and do infect domestic birds. Domestic birds are in closer contact with humans.

What are some outbreaks of bird flu in recent history?

There have been outbreaks of versions of bird flu all over the world. Some forms have a mortality rate that exceeds 50%. Recent outbreaks have happened in China and Russia. Previous pandemics related to bird flu include the following outbreaks.

  • The 1918 pandemic (the Spanish flu) resulted in 50 million people dying throughout the world was later linked to an H1N1 influenza virus that came from birds. The number of deaths in the U.S. was about 675,000.
  • The 1957-1958 pandemic was caused by the H2N2 virus, which originated from a bird influenza virus. This pandemic was called the Asian flu, as Singapore and Hong Kong were the first places to report infections. It killed 1.1 million people globally. Deaths in the U.S. totaled 116,000 people.
  • In 1968, the H3N2 flu virus caused a pandemic that killed 1 million people throughout the world. It was particularly serious for people over the age of 65. In the U.S, about 100,000 people died.
  • In 2009, the H1N1pdm09 virus, a novel H1N1 virus, was found in the U.S. This pandemic claimed an estimated 151,700 to 575,400 lives throughout the world in the first year it was in circulation. The numbers for the U.S. during the first year amounted to an estimated 12,469 deaths. The difference with this virus is that it caused more severe illness and death among people younger than 65 years old.

It’s impossible to eliminate bird flu from wild birds. The best approaches to bird flu currently include working to identify and eliminate outbreaks among domestic birds and to continue work on a vaccine that will be effective against bird flu.

A note from Cleveland Clinic

Cases of bird flu in humans have happened globally for quite a long time and are expected to continue into the future. If you’re traveling to places where bird flu exists, avoid visiting farms or open-air markets that sell poultry. If you feel sick after being in this type of situation, contact your healthcare provider. There are antiviral medications to treat bird flu.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 01/22/2022.

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