Avian Influenza

This information is provided by the Centers for Disease Control and Prevention. For additional information about Avian Influenza please visit, the CDC website: http://www.cdc.gov/flu/avian/ or contact CDC at (800) CDC-INFO.

What is avian influenza (bird flu)?
Avian influenza is an infection caused by avian (bird) influenza (flu) viruses. These flu viruses occur naturally among birds. Wild birds worldwide carry the viruses in their intestines, but usually do not get sick from them. However, avian influenza is very contagious among birds and can make some domesticated birds, including chickens, ducks, and turkeys, very sick and kill them.

Outbreaks of avian influenza H5N1 occurred among poultry in eight countries in Asia (Cambodia, China, Indonesia, Japan, Laos, South Korea, Thailand, and Vietnam) during late 2003 and early 2004. At that time, more than 100 million birds in the affected countries either died from the disease or were killed in order to try to control the outbreaks. By March 2004, the outbreak was reported to be under control.

Since late June 2004, however, new outbreaks of influenza H5N1 among poultry have been reported by several countries in Asia (Cambodia, China [Tibet], Indonesia, Kazakhstan, Malaysia, Mongolia, Russia [Siberia], Thailand, and Vietnam). It is believed that these outbreaks are ongoing. Influenza H5N1 infection also has been reported among poultry in Turkey and Romania and among wild migratory birds in Croatia.

How does avian influenza spread among birds?
Infected birds shed influenza virus in their saliva, nasal secretions, and feces. Susceptible birds become infected when they have contact with contaminated excretions or with surfaces that are contaminated with excretions or secretions. Domesticated birds may become infected with avian influenza virus through direct contact with infected waterfowl or other infected poultry or through contact with surfaces (such as dirt or cages) or materials (such as water or feed) that have been contaminated with the virus.

Do avian influenza viruses infect humans?
Bird flu viruses do not usually infect humans, but more than 100 confirmed cases of human infection with bird flu viruses have occurred since 1997. Human cases of influenza A (H5N1) infection have been reported in Cambodia, China, Indonesia, Thailand, Turkey, and Vietnam. The World Health Organization (WHO) maintains situation updates and cumulative reports of human cases of avian influenza A (H5N1).

What are the symptoms of avian influenza in humans?
Symptoms of avian influenza in humans have ranged from typical human influenza-like symptoms (fever, cough, sore throat, and muscle aches) to eye infections, pneumonia, severe respiratory diseases (such as acute respiratory distress syndrome), and other severe and life-threatening complications. The symptoms of avian influenza may depend on which specific virus subtype and strain caused the infection. A laboratory test is needed to confirm avian influenza in humans.

Is there a risk for becoming infected with avian influenza by eating poultry?
There is no evidence that properly cooked poultry or eggs can be a source of infection for avian influenza viruses. Cooking kills germs, including the bird flu virus. The U.S. government carefully controls domestic and imported food products, and in 2004 issued a ban on importation of poultry from countries affected by avian influenza viruses. This ban still is in place.

What precautions can be taken to reduce the risk for infection from wild birds in the United States?
As a general rule, the public should observe wildlife, including wild birds, from a distance. This protects you from possible exposure to pathogens and minimizes disturbance to the animal. Avoid touching wildlife. If there is contact with wildlife do not rub eyes, eat, drink, or smoke before washing hands with soap and water. Do not pick up diseased or dead wildlife. Contact your state, tribal, or federal natural resource agency if a sick or dead animal is found.

What advice would you give someone traveling to an impacted area?
During travel, you should avoid contact with chickens and ducks, follow good health habits (such as frequent hand washing) and avoid "live markets," bird farms and partially cooked birds.

Where can I find out more information about Avian Flu?
For additional information about the Avian Flu, visit the Centers for Disease Control and Prevention web site:http://www.cdc.gov/flu/avian/ or the World Health Organization web site: