Influenza, or "the flu", is a moniker that has come, in the modern vernacular, to represent anything more severe then a cold but less severe than pneumonia. The reality is that a true influenza infection can be extremely debilitating. The influenza virus comes in many forms that continue to circulate in populations of animals, mainly waterfowl such as ducks or geese. The virus readily mutates, and if it mutates in just the right way, it can jump from one species of animal to another. These new hosts, confronted with a virus like none they have seen before, will either survive and develop life-long immunity or succumb to the virus and lose the race to reproduce. This biological dance has occurred throughout recorded history at relatively predictable intervals, when the promiscuous influenza virus has made its way around the world in epidemic waves.
Most recently, a specific strain of the virus, H5N1, has become disturbingly common in poultry populations in Asia. The first recorded appearance of this strain was in the bird flu epidemic that erupted in Hong Kong in 1997, killing six people and resulting in the destruction of almost every chicken on the island, about 1.5 million in all. Efforts to control that epidemic were successful, and the virus is thought to have retreated to its natural host, aquatic waterfowl, in the Guangdong, Hunan and Yunnan provinces in China, where it awaited an opportunity to return.
