9.8.26 Public Health Education Topic: Avian Influenza

Per CDC:

Key points

• Bird flu is a disease caused by avian influenza A viruses that usually spread between birds, not people.

• One subtype of bird flu, caused by avian influenza A(H5) virus, is spreading worldwide in wild birds and causing sporadic outbreaks in U.S. poultry and dairy cows. In addition to spreading to an increasing number of mammals, H5 bird flu has caused some rare human infections.

Types

Influenza type A viruses can be further classified into subtypes. Subtypes of avian influenza A viruses known to have caused human infections include H5, H6, H7, H9, and H10 viruses.

Exposure risks

Exposure to infected sick or dead animals is the main risk factor for getting bird flu. Exposure to surfaces contaminated with animal secretions/excretions also is another risk. Eating undercooked or uncooked poultry, eggs, or consuming unpasteurized milk from infected dairy cows, could also be an exposure risk for infection with avian influenza A viruses. Consuming properly prepared and cooked (or pasteurized) products is safe.

People at risk

People with close or prolonged contact with infected birds or other infected animals or contaminated environments, including people with job- or recreational-related exposures, are at greater risk of getting sick with avian influenza A viruses. Other things can impact whether you get very sick from bird flu, including older age, delayed medical care, and/or underlying medical conditions.

Signs and symptoms

The reported signs and symptoms of avian influenza A virus infections in humans have ranged from no symptoms or mild symptoms to moderate to severe disease and complications, including resulting in death.

Mild signs and symptoms may include:

• eye redness and irritation (conjunctivitis)

• mild fever (temperature of 100ºF [37.8ºC] or greater) or feeling feverish*,

• cough

• sore throat

• runny or stuff nose

• muscle or body aches

• headaches

• fatigue

Eye redness has been the predominant symptom among recent U.S. cases of avian influenza A(H5) virus infection.

Less common symptoms include diarrhea, nausea, or vomiting.

*Fever may not always be present

Signs and symptoms of moderate to severe disease

• high fever

• shortness of breath or difficulty breathing

• altered consciousness.

• seizures

More information about symptoms of avian influenza A(H5) virus infections in people, including timing of symptoms, and complications, is available at Signs and Symptoms of Bird Flu in People.

To learn more please visit: About Bird Flu | Bird Flu | CDC