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Bird Flu Virus : Bird Flu Facts
Bird Flu MortalityBird influenza is an infectious disease of birds caused by type A strains of the influenza virus. The disease takes place worldwide. While all ..... Birds’ influenza is an infectious disease of birds caused by type a strains of the influenza virus. The disease, which was first identified in Italy more than 100 years ago, takes place worldwide. All birds are thought to be vulnerable to infection with avian influenza, though some species are more resistant to infection than others. Infection causes a wide range of symptoms in birds, ranging from mild illness to a highly contagious and rapidly fatal disease resulting in severe epidemics. The latter is known as extremely pathogenic bird influenza. This form is featured by sudden onset, severe illness, and rapid death, with a mortality that can approach 100%. Extensive investigation of that outburst determined that close contact with live infected poultry was the source of human infection.
Fifteen subtypes of influenza virus are recognized to infect birds, thus providing an extensive reservoir of influenza viruses potentially mingle in bird populations. To date, all outbreaks of the highly pathogenic form have been sourced by influenza a viruses of subtypes H5 and H7. Migratory waterfowl most particularly wild ducks are the natural reservoir of bird influenza viruses, and these birds are also the most resistant to infection. Domestic poultry, including chickens and turkeys, are chiefly susceptible to epidemics of rapidly fatal influenza. Direct or indirect contact of domestic flocks with wild migratory waterfowl has been concerned as a frequent cause of epidemics. Live bird markets have also played a vital role in the spread of epidemics.
The quarantining of infected farms and destruction of infected or potentially exposed flocks are standard organize measures aimed at preventing spread to other farms and eventual establishment of the virus in a country’s poultry population. Apart from being highly contagious, bird influenza viruses are readily transmitted from farm to farm by mechanical means, such as by contaminated equipment, vehicles, feed, cages, or clothing. Highly pathogenic viruses can stay alive for long periods in the environment, especially when temperatures are low. Stringent sanitary procedures on farms can, however, confer some degree of protection. In the absence of prompt control procedures backed by good surveillance, epidemics can last for years.
Bird Flu FactsBirds’ influenza is an infectious disease of birds caused by type a strains of the influenza virus. The disease, which .....
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