Diseases of avian influenza transmitted from poultry to poultry, from birds to humans and are restricted from human to human. Although until now there has been no contact by direct and indirect contacts possible.
A. Transmission Between Poultry
Diseases of avian influenza can be transmitted through contaminated air H5N1 viruses originating from feces of sick birds. Transmission can also occur through drinking water and food that has been contaminated by feces of infected avian influenza.
In poultry farms, transmission can occur through the mechanical equipment, cages, clothing, or shoes that have been exposed to avian influenza virus (H5N1), also the farm workers.
B. Transmission from Birds to Humans
Transmission of avian influenza viruses from poultry to humans may occur when human contact with poultry infected with avian influenza virus. Or with objects contaminated by their faeces which contain the virus H5N1 illness.
Until now, cases of avian influenza in humans is more common in rural areas or cities with dense population. In this area removable and fowl are kept in a cage not included. Many birds found in the home cage or where children play. With these conditions it is very possible transmission from sick poultry to humans, because in the feces of sick birds have the H5N1 virus.
C. Inter-Human Transmission
Until now, transmission of avian influenza virus (H5N1) from humans to humans has not occurred. This transmission model is likely to occur, although not efficient, Because all influenza viruses have the ability to change genetically. Transmission of influenza A (H5N1) among human characterized with infected people in one group as in family, school or office. This is called a cluster.
D. Transmission of the Human Environment
Theoretically, this transmission model could be due to the H5N1 virus can survive in nature or the environment. Transmission that occurs because the water is contaminated by avian influenza viruses into humans through the mouth when the nose by swimming or water contaminated with feces from poultry infected with H5N1 virus. Poultry litter, especially the chicken which is usually used as a fertilizer plant is one risk factor for the spread of avian influenza.
E. Transmission to Other Mammals
Avian influenza virus (H5N1) can spread directly on several different mammals, namely pigs, horses, marine mammals, lions, tigers, cats, and ferrets.
According to the research that has been done, the pig does not play an important role in avian influenza caused by H5N1 virus in Asia.