Bird flu "Hong kong"

The recent outbreak of Hong Kong "bird flu" has focused new attention on the threat of influenza which has so far killed four people. What makes it so worrisome is that the virus responsible for the Hong Kong deaths and chicken slaughter contains a unique combination of proteins on its outer shell that renders it unrecognizable to the human immune system

The influenza virus changes the outer proteins on its shell, known as antigens, easily. The changes occur because the influenza virus lacks the genetic proofreading ability seen in many more stable viruses. When it makes an error in reproducing its own genetic material, the influenza virus passes along these errors to progeny viruses. In these ways, even a tiny error becomes permanent or as permanent as a mutable agent like the flu virus is likely to become.

Today's H5N1 influenza seems to be different. It is capable of making people sick. Nearly two dozen people of Hong Kong have come down with influenza as a result of exposure to chickens resulting in four deaths. No one yet knows exactly how H5N1 has changed, but it apparently has. As a result, the virus has become a big threat to the mankind. Fortunately, Hong Kong health authorities are taking the threat seriously. They have slaughtered more than 1.3 million chickens, as well as other poultry raised near chickens, and have banned importation of chickens from mainland China, despite the economic and political hardships.