Current Situation: H5N1 Bird Flu in People

Current H5N1 bird flu situation in people in the US

H5N1 bird flu is widespread in wild birds worldwide, has caused poultry outbreaks in many countries, and infected other kinds of animals. H5N1 bird flu has caused outbreaks in poultry and dairy cows in the United States with several human cases identified. While the current public health risk is low, CDC is watching the situation carefully and working with states to monitor people with animal exposures. CDC is using its flu surveillance systems to monitor for H5N1 bird flu infections in people.

Most H5N1 bird flu infections in humans in the United States have resulted in clinically mild illness, but a few hospitalizations and one death have been reported. Many people infected with avian influenza A(H5N1) viruses have reported unprotected workplace exposures, such as contact with infected or sick dairy cows or poultry without using recommended personal protective equipment. However, some human cases involved exposure to backyard poultry or wild birds, and in some cases, the exposure source could not be identified. CDC maintains a H5 Bird Flu: Current Situation page that has updated totals of human cases of H5N1 bird flu that have been identified in the United States, including a breakdown by exposure source and location. More information is also available from CDC spotlight articles.

The current risk to the general public is low

No known person-to-person spread has occurred with the avian influenza A(H5N1) viruses that are currently spreading in birds in the United States and globally. In other countries, sporadic human infections with the avian influenza A(H5N1) viruses have been reported, mostly following exposure to infected poultry.

What could change the public health risk

Detections that could raise the public health risk include multiple, simultaneous reports of human infections with avian influenza A(H5N1) viruses following exposure to birds or other animals, changes in the viruses that indicate increased ability to infect people or spread among people, or identification of sustained person-to-person spread.

Current H5N1 bird flu situation in people globally

Sporadic human infections with avian influenza A(H5N1) viruses have occurred worldwide since 1997, with high mortality, generally following direct or close exposure to infected sick or dead poultry. For more information on past reported human infections with avian influenza A viruses, visit: Reported Human Infections with Avian Influenza A Viruses.

People who are at higher risk of infection

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

How people get infected

Avian influenza (bird flu) Type A viruses do not normally infect people, but rare human infections have occurred with some avian influenza A viruses. More information is available at Bird Flu: Causes and How It Spreads.

Symptoms and illness severity

Illnesses in people from avian influenza A virus infections have ranged in severity from no symptoms or mild illness to severe disease that resulted in death. More information is available at Signs and Symptoms of Bird Flu in People.