Saturday, June 11, 2005

Chinese bird flu situation

The New York Times is reporting today that there is simultaneously more concern about the new H5N1 outbreak in domestic and migratory geese in China (Qinghai and Xinjiang) because these birds don't normally succumb to the virus, and somewhat less concern about reports of human cases.

Regarding the human health implications of the goose problem, three things are of concern. First, the fact that the virus seems highly virulent for a previously unaffected avian species suggests there has been an unpredicted and unexpected change in the virus. The behavior of the Chinese form also seems to have divered from that of the one in Vietnam and southeast asia. Thus the virus is unstable and unpredictable. Second, the outbreaks far into western China demonstrate even more forcefully that H5N1 infection has developed into a regional panzootic (pandemic in animals). Third, this panzootic increases the probability of other changes and interactions with additional species, including humans and other mammals.

With respect to the unverified reports of human cases, there is reason to be cautious in both directions. As we noted earlier, Qinghai province is a politically complex mixture of muslim, Chinese and Tibetan ethnicities, and the source of the reports was a dissident ex-patriate site that warned its reports were unverified. On the other hand, given the stakes, the situation and China's past record in the 2003 SARS episode, some amount of skepticism is warranted when Chinese officials deny such reports. It is a graphic example of the extraordinary difficulty of regaining trust once it is lost. One hopes this lesson is not lost on other governments, but in truth they have likely not learned from China's (continuing) experience.

China is claiming to be taking strict quarantine and control measures, with restricted travel into and out of the affected regions. Meanwhile, WHO has officially requested approval of a trip with Chinese health officials to Qinghai. The Chinese say they will grant it and that there will be complete freedom of travel for international health officials.

But it has yet to happen. We shall see.