The head of the World Health Organisation, the former Norwegian prime minister Ms Gro Harlem Brundtland, has punctured official optimism that the SARS outbreak is coming under control.
She said yesterday the epidemic has not yet peaked in China and it was too early to say whether the outbreak was receding worldwide.
"We can't say with any certainty whether the total picture of the outbreak has peaked or not. Certainly, we have not seen a peak in China yet. We still have a considerable size of outbreak in Hong Kong," Ms Bruntland said, prior to an emergency meeting in Brussels of EU health ministers.
She said the flu-like Severe Acute Respiratory Syndrome outbreak was over in Vietnam and on its way down in Canada.
In Beijing, WHO officials are still complaining that despite high-level promises of full disclosure, the Chinese authorities are holding back vital information.
Ms Mangai Balasegaram, a spokeswoman for the WHO's Beijing office, said the city's authorities still don't fully understand the course of the epidemic.
Critically missing in many cases, Ms Balasegaram said, is information gathered when patients fell sick.
Thus, she said, the city still isn't able to identify patterns in the outbreak, whether a few highly contagious individuals, known as super-spreaders, are causing many cases, or whether certain neighbourhoods or buildings in the city account for a disproportionate number of the infected.
The virus that causes SARS is spread mainly through face-to-face contact, but research indicates it can survive on surfaces for more than a day, and can also be transmitted through faeces. Without proper data, WHO experts say, the city would be unable to determine on patterns of the virus transmission and cut off the chains of infection.
The Prime Minister, Mr Wen Jiabao, admitted China's plight remained "grave" despite stepped-up prevention, detection and treatment of the disease which has struck hardest in Beijing, where almost 1,900 cases have now been confirmed.
"Beijing has made progress in the fight against SARS but the situation still remains grave," the official Xinhua news agency quoted Mr Wen as saying.
"A great deal of arduous work has to be done to bring the epidemic under control at an early date."
China's Health Ministry announced 138 new cases of SARS yesterday. It also reported eight more deaths, taking the toll in the world's most populous and worst-hit nation to 214.
The disease has killed at least 214 Chinese of 4,409 reported cases, out of 7,000 people infected and almost 500 dead worldwide.
Motorola closed its China headquarters in Beijing after a staff member caught the disease, dealing a fresh blow to business confidence.
Other foreign firms have closed offices or pulled employees out of China.
In Beijing's Haidian district, which has more SARS cases than any other, some 30,000 investigators in 4,000 teams made rolling inspections of businesses, neighbourhoods and work sites. Twenty patrols have the job of making continuous examinations of the many construction sites where China is constructing a high-tech Silicon Valley.
Local authorities across the country are taking extreme measures to stop the infections spreading. The eastern city of Nanjing has put nearly 10,000 people in quarantine, although only 600 of them have been in actual direct contact with the one confirmed case and four suspected. There are now a dozen different quarantine centres around the city.
Counties in Hebei province bordering Beijing have simply dug holes into the highways to stop traffic from Beijing. Visitors, no matter who they are, are being detained for up to 14 days in some provinces and localities.
As regions scramble to build and equip isolation wards to house suspects, they have selected remote areas only to find the locals responding with protests and riots.
At the weekend, more than 100 peasants attacked a government office in Yuhuan county, in eastern Zhejiang province, and beat up officials in a fury that a SARS quarantine centre would be opened in their community, the local Jianghuai Morning Post reported. Only three cases have been reported in Zhejiang.
In another incident, villagers in Linzhou city in central Henan province, looted and destroyed a planned SARS quarantine centre and moved on to ransack the local health station. The riots in Linzhou took place between April 25th and April 28th, the China News Service said.
There are just 14 confirmed cases in Henan In a third reported incident, peasants in Xiong county, central Hebei, cut off the electricity to an old people's home-turned-quarantine centre and five suspected SARS patients availed of the chance to escape.
"We had to move the elderly out of the facility and get the SARS-suspected patients in as soon as possible," Dr Wen Bo, director of Gugezhuang hospital, said according to a report in the Beijing Star.
"But when our patients arrived in the evening there was no power, it took a while to restore the electricity supply and then we discovered that some of them had used the disturbance to flee."
In Hebei province, SARS cases have tripled over the past week and now stand at 98 confirmed cases and six deaths.
Ten officials from Zhuozhou, in Hebei province, including the directors of the city's health bureau and its disease-control centre, have been sacked after they failed to prevent a feverish woman who had returned from Beijing from infecting her family and others.