Author Topic: Avian Influenza  (Read 2426 times)

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Avian Influenza
« on: April 04, 2015, 07:54:55 AM »
Avian influenza ("bird flu") is an infectious disease of birds caused by type A strains of the influenza virus. The infection can cause a wide spectrum of symptoms in birds, ranging from mild illness, which may pass unnoticed, to a rapidly fatal disease that can cause severe epidemics.

Avian influenza viruses do not normally infect humans. However, there have been instances of certain highly pathogenic strains causing severe respiratory disease in humans. In most cases, the people infected had been in close contact with infected poultry or with objects contaminated by their faeces. Nevertheless, there is concern that the virus could mutate to become more easily transmissible between humans, raising the possibility of an influenza pandemic.

Avian influenza (AI) is an infectious viral disease of birds (especially wild water fowl such as ducks and geese), often causing no apparent signs of illness. AI viruses can sometimes spread to domestic poultry and cause large-scale outbreaks of serious disease. Some of these AI viruses have also been reported to cross the species barrier and cause disease or subclinical infections in humans and other mammals.
The A(H5N1) virus subtype, a highly pathogenic AI virus, first infected humans in 1997 during a poultry outbreak in Hong Kong SAR, China. Since its widespread re-emergence in 2003 and 2004, this avian virus has spread from Asia to Europe and Africa and has become entrenched in poultry in some countries, resulting in millions of poultry infections, several hundred human cases, and many human deaths. Outbreaks in poultry have seriously impacted livelihoods, the economy and international trade in affected countries.

The A(H7N9) virus subtype, a low pathogenic AI virus, first infected 3 humans - 2 residents of the city of Shanghai and 1 resident of Anhui province - in March 2013. No cases of A(H7N9) outside of China have been reported. Containment measures, including the closure of live bird markets for several months, have impacted the agriculture sectors of affected countries and international trade. Continued surveillance for A(H7N9) will be necessary to detect and control the spread of the virus.

Ongoing circulation of A(H5N1) and A(H7N9) viruses in poultry, especially where endemic, continues to pose threats to public health, as these viruses have both the potential to cause serious disease in people and may have the potential to change into a form that is more transmissible among humans. Other influenza virus subtypes also circulate in poultry and other animals, and may also pose potential threats to public health.

Source: CDC, WHO

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Re: Avian Influenza
« Reply #1 on: April 04, 2015, 08:15:01 AM »
 :-[