TORONTO — The number of people with SARS in Canada's largest city tripled to 33 on Thursday when health officials broadened their definition of what constitutes a "probable case" to meet international standards.
The change came after the World Health Organization on Wednesday urged Canada to expand its definition of severe acute respiratory syndrome.
The new cluster of cases in Canada, first detected last week, was a harsh blow to a health-care system that appeared to have brought an initial SARS outbreak in March and April under control. Health officials have told more than 7,000 people to quarantine themselves due to possible exposure.
Meanwhile, Taiwan reported its lowest daily number of new SARS cases in three weeks today, and officials said that supported their view that the illness was fading on the island, ranked No. 3 in the world in deaths and infections.
But Friday's low number came just a day after Taiwan reported 50 new infections, the biggest increase in nearly a week.
The global death toll Thursday from SARS was at least 753, out of more than 8,300 people infected since November, mostly in China and Hong Kong.
Because of the new cluster in Canada, Toronto was placed again on WHO's list of SARS-affected areas. Another 29 cases were listed as suspected, and officials warned 107 other people showing possible SARS symptoms were being monitored.
"I think a large number of them will eventually be suspect or probable cases," said Dr. Donald Low, chief microbiologist at Mount Sinai Hospital and a key figure in Toronto's anti-SARS efforts.
Officials worry the WHO could issue another warning against travel to the city, like one on April 23 that was lifted a week later. WHO spokesman Iain Simpson said Thursday the U.N. agency was not considering another travel advisory yet.