The pneumonia-like virus Sars claimed at least a dozen new victims across Asia and one in Canada on Saturday, bringing the worldwide toll to more than 290.
Hong Kong has launched a poster campaign about Sars
Seven more deaths were reported in China and six in Hong Kong - including the territory's youngest victim - and there were hundreds more reported sufferers.
The wave of criticism of China's handling of Sars, or Severe Acute Respiratory Syndrome, has now also led to the resignation of Health Minister Zhang Wenkang, China's Xinhua official news agency reported.
US President George W Bush spoke by telephone to Chinese Premier Hu Jintao, and offered condolences to the families of those who have died from the Sars virus.
He said the US would offer "assistance" to China, if required.
Regional efforts to combat the disease took a step forward on Saturday, as health ministers from east Asia met in the Malaysian capital Kuala Lumpur.
They agreed there is a need for compulsory screening of passengers leaving their countries, but did not agree on common procedures.
The ministers from the 10-member Asean group, together with China, Japan and South Korea, also agreed:
not to impose blanket restrictions on accepting travellers from countries affected by the virus
to ask the World Health Organization (WHO) to refine its rules governing the issuing of travel advisories
to share more information, particularly to allow the movements and contacts of infected people to be traced internationally
KNOWN DEATH TOLL
Mainland China: 122
Hong Kong: 121
Source: WHO/ local health authorities
Ministers even agreed to swap personal cell phone numbers, the BBC's Jonathan Kent reports.
Canada, the only country outside Asia to have been badly hit by Sars, sent observers to the meeting.
A 77-year-old man died of the disease in Toronto on Saturday. He was the husband of a health care worker who had contracted the disease earlier.
But a World Health Organization (WHO) spokesman said the body was considering lifting its advice against travel to Toronto, where all of Canada's Sars deaths have occurred.
The Asian health ministers said in a statement they were "convinced of the effectiveness of screening of passengers before they leave affected areas in preventing the
spread of Sars".
"Even one single infectious case can lead into a serious outbreak unless rigorous measures are taken," they said.
Vice Premier Wu is taking charge of Sars response
Earlier, a WHO official said the countries had to be "absolutely relentless" in the fight against Sars.
In China, the Sars crisis continued to intensify with the resignation of Health Minister Zhang.
He has been replaced by Vice Premier Wu Yi - the most senior woman in Chinese politics and an internationally respected stateswoman.
Her appointment, says our correspondent Francis Markus, indicates how seriously authorities are taking the situation.
Seven new deaths in China took the death toll there on Saturday to 122, said the health ministry, with an additional 154 new cases.
In Hong Kong, there were six more deaths and 17 new cases reported.
Those who died included a 28-year-old man, believed to be a computer engineer who lived in Kowloon - the youngest victim in the territory so far.
His girlfriend told a local newspaper that his symptoms were minor at first, but his condition deteriorated earlier this month.
A BBC correspondent there says health officials are particularly concerned about the spread of Sars in the Amoy Gardens area, where the man lived. Several cases are reported among people who had had no contact with other Sars patients.
In other developments:
The WHO says Vietnam - which has reported no new cases of Sars in 18 days - could be declared the first country to have contained its outbreak
Italy places three people - two of them Chinese women and one an interpreter who recently returned from China - under observation after showing Sars symptoms
An Elton John-Billy Joel concert scheduled for Monday night at the Air Canada Center in Toronto is called off
Death rate higher?
A leading UK authority on infectious diseases in Hong Kong may amplify concerns when he completes a study of the outbreak.
Professor Roy Anderson, from Imperial College London, is carrying out the first detailed analysis of the spread of the virus there.
His study is expected to show that the virus has a higher death rate than the 5% previously estimated by the WHO.
WHO statistics currently show a death rate of just under 8% in Hong Kong and about 6% worldwide.
Another study, published in New Scientist magazine, estimated the death rate could turn out to be as high as 10%.
Professor Anderson's study suggests that Sars remains infectious for longer than many other viruses, our correspondent says.
But it may also find that the virus is harder to transmit from person to person than previously thought.
"This is not a highly transmissible infection," he told the BBC.