Situation in China: Jasper Becker, in Beijing, reports that the possibility of an even greater health crisis could call for much tougher measures.
Every night people in Beijing are stopping everything to watch a news programme, Focus Talk (Jiaodian Fangtan), that announces what new areas of the capital have been placed under quarantine.
On Friday night's list are the Carrefour supermarket, the Ditan Hospital, the Chaowai market, the Oriental Plaza, the 18th floor of the World Trade Centre, all famous landmarks in the city.
Officially the municipal government says 4,000 people have been forcibly quarantined, but it could be many more.
Many believe city officials already armed with emergency powers could declare a state of martial law, although this merely means that troops will be brought in to quarantine the city.
A new decree issued on Tuesday empowers imprisonment of up to seven years for those who refuse to comply with the orders of municipal or district health departments.
"I solemnly tell you that it is rumour. We absolutely will not seal our airports and highways, and we also absolutely will not impose any sort of martial law," Mr Cai Fuchao, a spokesman for the Beijing government, told a news conference.
The government now says Beijing has 877 Severe Acute Respiratory Syndrome infections, up from just 37 last Saturday, before the health minister and Beijing mayor were fired for covering up the extent of the outbreak.
Among the reports not being publicised is the news of three deaths in a suburb of Beijing, the Gaobeidian area, where foreigners come to buy "new antique" furniture made by low-paid chippies brought in from rural areas.
"Thousands of terrified workers have fled the workshops. And when the news spread, lots of others left, too scared to be quarantined," said a friend.
No one wants to be cooped up in an area where the mysterious virus is present, but an exodus of migrant workers is going to make the disease impossible to control. Across the country, provincial officials even in places as remote as Tibet are throwing up roadblocks and spraying vehicles.
In north-west China's obscure Ningxia Hui Autonomous Region, authorities have set up 21 "checkpoints" along major highways and at railroads and airports across the region to conduct medical examinations of SARS suspects. All motor vehicles in and out of Ningxia have to be disinfected.
Hospitals above the county level in Ningxia have designated special quarters for patients with their body temperatures higher than normal. Although they have received 105 such patients, none has been diagnosed as having SARS.
The fear that a greater health crisis is just over the horizon in rural China may prompt Madame Wu Yi, who has been appointed the commander-in-chief of the health campaign, to take much tougher measures.
The childless politburo member, who made her mark by running an extremely ruthless campaign to enforce the one-child policy over 10 years ago, has the right experience. She made officials under her forcibly arrest women and subject them to late-term abortions and ordered that peasants who had already flouted the rules should lose their homes and livestock.
Ouitside China, the Philippines reported its first deaths from SARS, and authorities in Taiwan quarantined over 1,000 doctors, nurses and patients in a hospital to halt the spread of the deadly flu-like disease.
A World Health Organisation official said SARS could become a horrifying epidemic if it spread in China's provinces or in nations like India and Bangladesh, where people live cheek-by-jowl and medical facilities are poor.
"There will be various countries in the world where we would be really concerned because we don't think they have the capacity to stem the tide once it is introduced," Mr Wolfgang Preiser told reporters in Shanghai. "It may have happened already, we don't know."
Taiwan authorities sealed Taipei Municipal Ho Ping Hospital on Thursday after more than 25 suspected SARS cases were discovered, and about 1,000 doctors, nurses, patients and visitors will have to stay there for up to two weeks.