Since the first bird flu case in the world was recorded in 1878, for the next 100 years the disease did not infect people until 1997, when it killed six in Hong Kong. And it has killed around a dozen Vietnamese this year. In addition, this winter's SARS cases in south China's Guangdong Province are suspected to be related to masked civets. Chinese scientists therefore say we should strengthen the study of animal viruses, especially their relationships to human diseases.
Since the 1970s, around 35 new infectious diseases have emerged around the world, such as AIDS and SARS, of which the major sources of infection are most likely animals.
Studies also show that normally the bird flu does not infect people. Guo Yuanji, a virology professor from the Chinese Center of Disease Control, says that more research needs to be done on the connection between animal viruses and human diseases.
"In the case of Viet Nam, the death rate of bird flu in humans is around two thirds, twice that in Hong Kong in 1997. But in South Korea and Japan, there are as yet no reported cases of human infection. We should closely observe the situation in these two countries, and do more lab research to find out how the virus is transferring from animals to humans."
But Professor Guo Yuanji notes that one thing is sure: humans contract bird flu through physical contact. At present, there are no known cases of people contracting it by eating chicken or eggs. He also tends to agree that people are infected through direct and close contact with domestic fowl or wild birds, not by an intermediary of livestock, such as pigs.
But as a precautionary measure, Professor Guo Yuanji says concerning the situation in China he does not favor keeping pets.
"We often see dogs defecating and urinating in the streets. It should be forbidden, as the excrement and urine of animals usually contain lots of viruses. If you have a pet, you should pay more attention to personal hygiene. Pensioners, children and sick members of your family should keep away from the pet, especially when the pet is sick."
Chinese scientists say that, from the technical perspective, bird flu vaccine for humans could be made available, but the current situation in China, as well in other countries and regions, is not so serious as to justify its mass production and application. They also suggest that people take some common flu medicines for prevention and early treatment.
(CRI January 16, 2004)
