The Race To Contain A Virus

Officials at the Guangdong CDC, while confident that culling the civets was necessary, are not totally convinced that it will curtail an outbreak. They have ordered a further extermination of rats--a much more elusive target--because of evidence that they carry a similar virus. Dr. Rob Breiman, an epidemiologist from the U.S. Centers for Disease Control and Prevention, is leading the WHO team currently tracing the origins of last year's epidemic in Guangdong. Breiman observes, "Everyone certainly thinks this is meaningful. But where is the civet cat in the chain? Are they getting it from another animal? Are civet cats infecting rodents as well as humans? We just don't know exactly where civet cats fit in." But he concedes, "From a political and public-health standpoint, it was a reasonable step in response to the re-emergence of SARS this year to act on the most likely source."

Yi's American mentor, Dr. Robert Webster of St. Jude's Children's Research Hospital in Memphis, Tenn., a pioneer in establishing the zoonotic origins of many influenzas, says, "The research is solid, but still, Yi has certainly stuck his neck way out there on this one." Yi, as usual, is dismissive of any doubts. Back in Hong Kong, he explains how the virus found in other animals such as badgers is genetically less similar to the strains found in humans, before vowing that culling civets "will break the chain of infection."

The incubation period for SARS is 14 days. The last civets were taken from the wild-animal markets on Jan. 6. By Jan. 20, if no new human cases emerge, we will have a very good indication if Yi, and the Guangdong government, made the right call. --With reporting by Jodi Xu/Guangzhou