The avian influenza virus causes avian bird flu in humans. Primarily found in the intestines of wild birds, these viruses rarely affect them. The avian bird flu virus in domestic poultry, however, is transmittable to human beings and can be fatal if not detected and treated on time. The World Health Organization (WHO) identifies "low pathogenic" and "highly pathogenic" as two main forms of the bird flu diseases in domestic poultry caused because of H5 and H7 subtype of influenza viruses. Over a period of time, these viruses have mutated, enabling them to infect humans. Virus H5N1, which has this capability, is responsible for the present outbreak affecting numerous countries across the globe.
History of Bird Flu
The first case if avian bird flu was identified in Italy in 1878. Separate research conducted by Sir John Skehel of the National Institute for Medical Research in London and Prof. Ian Wilson of the Scripps Research Institute in San Diego concludes that the 1918 Spanish flu was because of bird flu, and the same disease was also responsible for the death of six people in 1997 in Hong Kong. The present outbreak again emerged in 2003 in Hong Kong and later spread to other parts of the world.
Transmission to Humans
By April 21, 2010, the WHO had recorded a total of 495 confirmed cases of transmission of Avian Influenza A (H5N1) to humans, 292 of which resulted in death. According to the Centers for Disease Control and Prevention (CDC), H5N1 is transmitted from poultry to humans in two ways: direct contact with infected birds and objects contaminated by their fecal matter. Unhygienic handling of food poultry products is another way in which the virus transmits itself. The virus, however, cannot be communicated through cooked food. Whether migratory birds transmit the virus is still questionable; however, the possibility cannot be ruled out, the WHO states.
Pandemic Risk
While the WHO maintains that the virus does not spread from birds to humans easily, the danger of pandemic is not remote. It can be a real threat if a new subtype of the virus emerges with the capability of transmitting itself from one person to another. The continuing proliferation of H5N1 in domestic poultry is a serious concern for the world at large. Though no avian bird flu infections have been reported in the United States, if the virus mutates again and is able to spread easily between humans, the threat of pandemic is possible.
Treatment and Vaccines
Treatment for avian flu virus varies and primarily depends on the symptoms and type of virus, a report published by The New York Times states. Zanamivir or oseltamivir reduce the severity of the disease if they are administered within 48 hours of the appearance of symptoms. The CDC, on the other hand, reports that the H5N1 virus can be resistant to common antiviral medicines like amantadine. Effectiveness of Zanamivir and oseltamivir needs further study as well. The New York Times report also says a vaccine for the flu virus already has been approved by the U.S. Food and Drug Administration.
Is the World Prepared?
According to WHO, it is not. The supranational organization has advised every country, including the United States, to have its own plan in case of a flu pandemic. It also advocated that more "well-off" countries stash adequate supplies of antiviral medications.
References
- World Health Organization: Avian Influenza FAQs
- Avian Influenza: Bird Flu Origins
- World Health Organization: Cumulative Number of Confirmed Human Cases of Avian Influenza A
- The New York Times: Avian Influenza
- Centers for Disease Control and Prevention: Transmission of Influenza A Viruses Between Animals and People
