China Threat

The disease becomes a world-wide catastrophe if it mutates in a way that allows it to be spread from human-to-human. Ironically, the disease would also be much more deadly if it was to mutate into a less deadly form. Because it kills half its victims, its spread is, to some degree, self-limiting. If it were to kill a much smaller percentage, say 1%, of its victims, it would be much more likely to spread across the globe, causing far more total deaths.

The widespread presence of the bird flu in China raises the risks of both of those developments.

First, China contains 20% of the world`s population. Most of the reported cases of flu outbreaks and deaths have been in Vietnam. The rural Chinese population, roughly 600 million, is over 10 times greater than that of Vietnam. The number of chickens is staggering. There are roughly 14 billion chickens in China.

Second, this is the flu season. Flu viruses, including the H5N1 bird flu, are able to survive up to 10 times longer during the winter months. The flu virus can only live for about 4 days in 70 degree weather. When the temperatures are around freezing, it can live for a month.

Normally, between 10 percent and 20 percent of the population are infected with the flu. In rural China, that would be between 60 and 120 million people.

While the typical mental image of China is of a warm climate, the climate in China is actually very similar to that of the U.S. Temperatures range from very cold in northern China to the mid 70`s in southern China. (See map below).

By contrast, Vietnam is relatively warm, with temperatures rarely dropping into the 50`s.

Pigs, which can get the flu from both birds and humans, can provide a host for a bird flu mutation to occur. China is the world`s largest producer of pork. Roughly half of the pigs in the world, over 450 million, live in China. By contrast, the U.S. pig population is around 60 million. Up to 80% of the Chinese pig production is in `backyard` operations. Families raise 2 or 3 pigs a year.

Taken together, the widespread presence of the bird flu in China, its huge population and the onset of the flu season mean that there is a far greater chance for a dangerous bird flu mutation to take place.

China - Winter Temperature Map