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Avian Influenza


What is avian influenza?

Avian influenza (commonly called bird flu) is a disease caused by viruses found in wild aquatic birds and domestic poultry.

What is the difference between influenza, avian influenza and pandemic influenza?

Influenza (often called "flu") is an illness caused by the influenza virus. Symptoms include fever, cough, muscle aches, headache, runny nose, sore throat and general weakness. These symptoms can range from mild to severe. It can be serious in the very young, the very old, and people who have other health problems.

Birds can also develop influenza, called avian influenza. The influenza viruses that affect birds (both wild and domestic) typically do not affect humans. Influenza in birds may cause no disease or mild symptoms, but can sometimes cause death to the bird.

Pandemic influenza ("pandemic flu") is a worldwide outbreak of a new type of influenza virus. A pandemic usually appears when an animal influenza virus changes or mixes with a human influenza virus to create a new virus. The new virus is able to spread easily from person to person. It can cause widespread illness because most people can get sick (they are not immune). 

What kinds of birds can develop bird flu?

All birds are vulnerable to bird flu. Migratory birds, such as wild ducks or geese, can carry the virus. These birds typically do not have symptoms but can still spread the disease. Domestic birds, such as chickens and ducks, can get avian influenza through direct contact with an infected bird's saliva, nasal secretions, or droppings (poop).

Can people get bird flu?

Although rare, humans can become infected with bird influenza. Those who had direct, close contact with infected birds or contaminated surfaces (such as bird droppings or respiratory secretions) can get bird flu. Most human infections have occurred through direct contact with live or dead infected poultry.

Can bird flu be transmitted from person to person?

Reports of cases of avian influenza transmitted from person to person are rare. To date, people who had bird flu could not pass it easily to other people. However, because bird flu viruses can change so they can be more easily passed between people, bird flu activity is closely monitored by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC).

Is bird flu common in the United States (U.S.)?

Bird flu that has caused illness in humans in the U. S. has been reported very rarely.  Several steps are being taken to prevent the spread of bird flu in the U.S. The USDA (United States Department of Agriculture) does not allow import of poultry or poultry products from areas affected by bird flu. In addition, all live birds or birds that have traveled to affected countries are quarantined for 30 days and tested for the bird flu when they return to the U.S. Bird flu can still be introduced into the country through migratory birds, illegally smuggled infected birds, or a person infected with a bird flu virus. Surveillance for disease among birds is done in live bird markets, commercial flocks, backyard flocks, and migratory bird populations. Health departments monitor for bird flu in humans.

What are the symptoms of bird flu?

The symptoms of bird flu may range from mild to severe. In a mild infection, the symptoms can range from conjunctivitis (infection of the eye) to general symptoms such as fever, cough, sore throat and muscle aches. In a severe infection, the symptoms can include respiratory illness (shortness of breath, difficulty breathing, and pneumonia), nausea, abdominal pain, diarrhea, vomiting, and sometimes neurological changes (confusion, seizures). Infection with a bird flu virus can be fatal.

How is bird flu diagnosed?

A laboratory test can confirm bird flu. Swabs taken from the nose or throat during the first few days of the illness can identify an infection.

How is bird flu treated?

Medications are available for treatment.

How can I protect myself against bird flu?

The best way to prevent infection is to take steps to avoid becoming infected where bird flu may occur. Most human infections with bird flu have been caused by direct or close contact with infected poultry. If you will be in direct contact with live poultry, wash your hands after any contact. People who work with live poultry flocks should use personal protective equipment. People should avoid direct contact with wild birds and observe them only from a distance. Avoid contact with poultry that appear ill or have died. Do not touch surfaces that appear to be contaminated with droppings from wild or domestic birds. If you are traveling in an area that is being affected by bird flu, you should avoid direct contact with poultry. For information on bird flu outbreaks and travel information, visit

Everyone 6 months and older should get vaccinated against seasonal influenza every year. Although the human influenza vaccine will not prevent infection with avian influenza, it may prevent getting infected with both human and bird flu viruses at the same time.

Is it safe to eat poultry?

It is safe to eat properly handled and cooked poultry in the U. S. Remember to always wash your hands after handling raw poultry. All poultry and poultry products (including eggs) should be cooked thoroughly before eating (safe internal cooking temperature for poultry is 165°F). Click here to learn more about food safety.



For more information about the bird flu, please visit the FDA or USDA website.

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