Health Articles : Infections : Bird Flu
Bird Flu Virus : Bird Flu Mortality
Bird Flu PandemicThe word pandemic is a combination of two Greek words pan meaning all and demos meaning people. It ..... Bird influenza is an infectious disease of birds caused by type A strains of the influenza virus. The disease takes place worldwide. While all birds are thought to be susceptible to infection with bird influenza viruses, many wild bird species carry these viruses with no apparent signs of harm. Other bird species, including domestic poultry, develop disease when infected with bird influenza viruses. In poultry, the viruses cause two clearly different forms of disease one common and mild, the other rare and highly lethal. In the mild form, signs of illness might be expressed only as ruffled feathers, reduced egg production, or mild effects on the respiratory system. Outbreaks can be so mild they escape detection unless and until regular testing for viruses is in place.
In contrast, the second and far less common highly pathogenic kind is difficult to miss. First identified in Italy in 1878, highly pathogenic bird influenza is featured by sudden onset of severe disease, rapid contagion, and a mortality rate that can approach 100% within 48 hours. In this kind of the disease, the virus not only affects the respiratory tract, as in the mild form, but also invades multiple organs and tissues. The resulting massive internal hemorrhaging has earned it the name of chicken Ebola. Not all virus strains of the H5 and H7 subtypes are highly pathogenic, but maximum of it are thought to have the potential to become so. Current research has shown that H5 and H7 viruses of low pathogenicity can, after circulation for sometimes-short periods in a poultry population, mutate into highly pathogenic viruses. Considerable circumstantial evidence has long suggested that wild waterfowl introduce bird influenza viruses, in their low pathogenic form, to poultry flocks, but do not carry or directly expand highly pathogenic viruses.
For highly pathogenic disease, the most significant control measures are rapid culling of all infected or exposed birds, proper disposal of carcasses, the quarantining and rigorous disinfections of farms, and the implementation of strict sanitary, or bio security, measures. Restrictions on the movement of live poultry, both within and between countries, are another significant control measure. The logistics of recommended control measures are most straightforward when applied to large commercial farms, where birds are housed indoors, generally under strictly controlled sanitary conditions, in large numbers. Control is much more difficult under poultry production systems in which most birds are raised in small backyard flocks scattered throughout rural or periurban areas.
Bird Flu MedicineBird flu can be defined as a disease that is caused by the virus called avian influenza virus. It is named .....
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