Guangdong province (Canton), China, is a beautiful place: lots of water, quite some green trees, numerous rice plots, and very hot. People have been living there for eons. But for many modern western people, Guangdong is known because of its neighbor– Hong Kong. Hong Kong is a nice (and rich) place too. But these days, Hong Kong is denigrated (again) by a vicious word—flu.
There are many different types of flu viruses–H1N1, H3N2, H5N1, and so forth, all named after their respecting hemagglutinin [HA] and neuraminidase[NA]. But one troubling thing is that they are also associated with lots of Chinese names: Hong Kong 111, Fujian 222, Guangzhou 333 etc.. Imagine that you hear the news paper reports “this winter we will have a deadly Fujian 222 virus,†it sounds like we Chinese somehow spread the virus to the world. What a bummer!
Sure the viruses are not spread by Chinese. The lots of Chinese names only suggest that they are isolated in China. But then another question arises: why are there so many?
The southern China, specifically Guangdong province, is the world renowned epicenter for flu virus (and many other flu-like and respiratory viruses). The notorious SARS has made Guangdong people, the Cantonese, world famous for their insatiate appetite and indiscriminating dietary choice. But in fact, Guangdong has been famous for years for its generating flu viruses.
In 1997, the first human case of avian flu occurred in Hong Kong. In that year, all chickens, both healthy and sick ones, were slaughtered to save the world. But the avian flu virus came back quickly to the Hong Kong local chick market. Hong Kong health department, correctly, fingered its neighbor as the source of avian flu virus. Clearing chicken and duck market in Hong Kong was no use if there was no similar measure employed in Guangdong.
In Guangdong, it has been a tradition that farmers raise chickens and ducks at home. In 1980s, awaken by the call from Deng’s money driven economic plan, the scale of family bird production increased significantly. A professional chicken raiser might have a thousand chickens. Chickens and ducks were usually raised in a semi-closed form. Ducks can swim river by river to rampage foods, and chickens are raised in open places. It is a booming business in a not so modern format.
The large number of birds and the close contact between birds and humans are the best combination for virus transmission. There are many bird flu viruses (avian flu virus) circulating among birds. In addition to the airborne transmission, chickens and ducks can be infected when they pass the farmland where sick birds have walked before. During flu seasons, it is very common to found half of the chickens dead when opening the gate in the morning. Certainly, there are many people contracted avian flu virus in Guangdong, but they are not reported due to insufficient monitoring system.
Because Guangdong province has an amiable climate and there are lots of small bird raising families, during the last thirty years, Guangdong has brought forth tens of new flu viruses to the world. The most recent one is the avian flu virus H5N1.
This year’s avian flu virus is actively circulating in the Southeast Asian where the chickens and ducks are raised in a similar way that Cantonese do. The virus has crossed to human beings several times since the first cross in Hong Kong in 1997. This is scary because the virus is constantly attempting to migrate to human beings. Even though it seems that the virus hasn’t successfully spread among human beings in a large scale, people are worrying about it because if by chance it develops a better strategy to spread among human beings, the virus may be unstoppable. There is no vaccine available yet, and the fatality till now is 60%.
It is not the end of world, that’s for sure. Last week the 1918 flu virus has been resuscitated. Its genome is also completely known by now. The bad news is that the virus directly jumped from birds to human beings in 1918, just like the recent H5N1. It also has high virulence which took away about 50 million people during the epidemic.
By studying the 1918 flu virus, we may be able to see how avian flu virus evolves to be able to jump from birds to human. With this knowledge, we may be able to develop drugs to specifically kill the virus. It is a great advance in influenza research.
There is also good news from Guangdong. The family bird raising business has been gradually replaced by modern facilities. We hope that fewer and fewer bird flu viruses cross to human beings in Guangdong.