The virus responsible for the Avian Flu is passed through saliva, nasal secretions, and feces of the bird that are affected. Some domesticated birds could be infected through contact with diseased waterfowl or poultry and the virus is also passed through things as simple as the dirt from cages of infected birds.

There are two main forms of disease caused by Bird Flu. The “low pathogenic” form may go undetected and usually causes only mild symptoms like ruffled feathers and a possible drop in egg production. The highly pathogenic form spreads more rapidly through flocks of poultry which affects multiple internal organs and causes death at a rate of 90-100 percent and can occur within 48 hours. How then does this affect human beings?

Avian influenza virus refers to the influenza type A viruses which is found mostly in birds and studies have shown, however that infections with these viruses can also affect humans. The risk from avian influenza is usually low because it is not normal for the viruses to affect humans. There have been more confirmed cases of human infection from several subtypes of avian influenza infection since the late 1990's.In many of these the cases have been in people who have direct contact with infected poultry such as domesticated chicken, ducks, and turkeys or they have had contact with surfaces contaminated with feces from infected birds. The spread of Bird Flu viruses from one person to another has been reported, transmission has not been seen to continue beyond one person but the medical community is concerned with the possibility that it could happen within a very short period of time. The concern is that if the virus is mutated and mutates far enough it could cause a pandemic over the world.

Human influenza virus usually refers to those subtypes that spread widely among humans. There are only three known type A subtypes of influenza viruses and they are H1N1, H1N2, and H3N2. 

When there is avian influenza around poultry, there is an increased possible risk to people who have contact with infected birds or surfaces that have been contaminated with secretions or excretions from infected birds to contract the virus. Studies have shown that many of the people who have been reported sick since the 1990's have had direct contact with domesticated birds of some description and there have been recent instances when cats have contracted the illness giving great concern to the world medical community.

Symptoms of Bird Flu in humans include fever, cough, sore throat, and muscle aches as well as eye infections, pneumonia, severe respiratory diseases and in some cases have caused acute respiratory distress and life-threatening complications. There is hope that some of the prescription medicines approved in the United States for human influenza viruses such as Tamiflu, will work in treating Bird flu infection in humans, however these drugs are currently in short supply.