Recent SARS cases may represent milder strain

GUANGZHOU, CHINA — GUANGZHOU, China - The three cases of SARS that have been identified here this winter might represent a milder strain of the disease, and the public health system appears well prepared to prevent a larger outbreak, a senior World Health Organization investigator said here yesterday.

Dr. Robert Breiman, the leader of a World Health Organization team that has been investigating the cases here, said that each of the three patients had been feverish for only eight to 12 days, had only shown signs of pneumonia on X-rays for a week and had never required ventilators


None of the three appears to have infected any of their families, friends or associates, who have been quarantined or closely monitored by local health officials, he added.

"What we've observed so far has been a little on the milder side," Breiman said at a news conference yesterday morning as he and the rest of the doctors on the team prepared to fly back later yesterday to the various national health agencies that had lent them to the WHO.


But he cautioned that some cases had been mild last year and that it might be a coincidence that the three cases this winter have also been mild. "It could be just the luck of the draw," he said.

Even if a more infectious or life-threatening strain appears, as happened last winter in southern China's Guangdong province and could occur again, the public health system seems much better prepared to isolate patients quickly, Breiman said.

"The lessons of 2003 were taken very much to heart," he said.

The first cases of severe acute respiratory syndrome were recorded in the suburbs of Guangzhou in November 2002, and it infected hundreds in the city by February. A Guangzhou doctor carried the disease in late February to Hong Kong, Asia's busiest air travel hub, and from there it swiftly spread around the world.

Breiman said that investigators here had found further evidence linking SARS to civets, a relationship first documented by Guangdong and Hong Kong experts and one that overseas doctors are starting to accept. At a restaurant where a 20-year-old waitress has contracted a suspected case of the disease, investigators used equipment provided by Canada's health ministry to test cages that used to hold civets, a relative of the mongoose that is a delicacy here, and found that almost all of the cages had traces of the virus believed to cause SARS.

Dr. Xu Ruiheng, the deputy director of the Guangdong Centers for Disease Control, said at the news conference that having killed civets at restaurants and in wild animal markets and on farms across the province last week, health officials are checking these places to make sure the trade in civets does not revive.