All of the new suspected cases have been traced to a single patient, the government said Sunday, suggesting the problem was still tightly confined. But it was an alarming reminder that the disease responsible for killing 349 people in China during last year's outbreak still poses a threat despite efforts by the government to make sure it didn't return.
The latest four cases announced the Health Ministry on its Web site brought the total for the past week to two confirmed and six suspected. The new suspected cases are the father, mother, aunt and roommate of a 20-year-old confirmed SARS patient in Beijing, the ministry said.
The other confirmed case of the past week is a 26-year-old medical student in the southern province of Anhui.
"According to the information we've gotten from the government, the transmission we've seen so far has been happening with ... people who have been in close contact with people who probably have SARS," Beijing-based World Health Organization spokesman Bob Dietz said Sunday.
"When we start to see `effective transmission' — spread through the general public through normal contact, not intense personal contact — that's when we feel we've reached another stage," Dietz said. "We haven't reached that stage. If it comes, we really are in something much more reminiscent of last year."
SARS first emerged in southern China in November 2002. It set off a global health crisis, killing 774 people around the world and infecting more than 8,000.
The Chinese government came under fire internationally for initially being slow to publicize information about the disease. It has promised to be more forthcoming.
The coming May Day holiday is a time when millions of Chinese travel within their borders on vacation. Many stream to Huangshan, a popular scenic mountain resort in Anhui, the province where one confirmed SARS case and one suspected death from the disease were reported Friday.
That got the attention of the province's Tourism Administration, which issued what it called an "emergency circular" on Sunday and called for "immediate action to prevent the spread of SARS." Provincial tourism offices were ordered to stay open "around the clock."
Beijing, China's capital, also reported one confirmed and one suspected case last week.
As it cautioned against panic, WHO agreed to dispatch a team of experts to help investigate links between a SARS research lab in Beijing and the severe acute respiratory syndrome cases being investigated last week — two of which involved lab workers.
The workers became sick at the research lab in the Chinese capital, WHO said. And in what could be the world's first SARS death this year, one worker's mother died last week in Anhui. Though Chinese authorities said she had a heart condition, WHO said she had "clinical symptoms ... compatible with SARS."
The daughter, a 26-year-old medical student surnamed Song, worked at the lab — the virus control institute at China's Centers for Disease Control — and is believed to have infected her mother after returning to Anhui.
Song was confirmed to have SARS and was treated last month at a Beijing hospital, where she came into contact with the 20-year-old nurse, surnamed Li, who is also now a confirmed SARS case, the ministry said. A 31-year-old Beijing man who worked at the lab has been listed as a suspected case.
Song "has been recovering" and her temperature was normal Sunday, the official Xinhua News Agency said. It said her other vital signs, including breathing, have been improving.
The lab has been sealed off. Several hundred of its employees and people with who had contact with the patients were quarantined in a hotel in Beijing's outskirts, state media said. More than 300 people who had contact with the cases in Beijing and Anhui have been quarantined.
China is particularly sensitive to outbreaks that coincide with economically pivotal national holidays, when millions of citizens travel by train, plane and car, creating a potential nightmare of disease vectors on the move.
Last year's Spring Festival took place just as the disease that would be named SARS was being noticed, and some said it helped spread the virus. The government cut last year's weeklong May Day holiday to five days and banned tourist travel because the country was in the throes of the outbreak.
China says it is screening thousands of travelers for fevers at airports and train stations in a massive effort to block a new outbreak.
There was no evidence of temperature screening for arriving international flights at Beijing's Capital Airport on Saturday night. Meanwhile, South Korea, which has been SARS-free, stepped up its inspections of travelers from Beijing and Shanghai.