TORONTO -- A suburban Toronto high school was closed and its 1,700 students and staff placed under quarantine after a student showed symptoms of SARS, health officials said Wednesday.
The move means more than 5,000 people in the Toronto area have been told to stay home for 10 days as authorities seek to control the spread of a new cluster of SARS cases known to have infected 11 people and to be suspected in 23 others.
Two more elderly patients died, raising the overall SARS toll to 29 deaths in the Toronto area in the biggest outbreak of severe acute respiratory syndrome outside of Asia.
Dr. Colin D'Cunha, the Ontario commissioner of public health who announced the deaths and latest figures, said 50 more cases were under investigation and the number of probable or suspected cases will rise.
"Absolutely there will be more in the next few days," said Dr. James Young, the province's commissioner of public safety.
Also Wednesday, the World Health Organization advised Canada to broaden its definition of severe acute respiratory syndrome cases after a health official expressed concern that the current one provided an incomplete account of the situation.
More cases expected
Dr. Donald Low, a microbiologist and key figure of the anti-SARS team dealing with the Toronto-area outbreak, said the number of new probable cases would be well over 20 -- rather than the current figure of 11 -- if officials used the same definition applied during the initial outbreak in March and April.
On the Health Canada Web site Wednesday, a probable case was defined as someone showing a severe progressive respiratory ailment -- a more serious condition than the WHO definition, a respiratory ailment visible on a chest X-ray.
Dr. Denise Werker of the WHO's communicable diseases section said discussions with Canadian health authorities Wednesday focused on the differing definitions.
"In the discussion that has just happened with Health Canada, we have advised them that...it would be prudent for them to have a case definition that is more sensitive than the one that they have currently," Werker told The Canadian Press from Geneva.
Dr. Paul Gully, a federal health official, said revising the case definition was under consideration. He conceded that changing Canada's definition of a probable case to match the WHO definition would cause some suspected SARS patients to be classified as probable.
The new SARS cases first made public last week put Toronto, Canada's largest city, back on a World Health Organization list of SARS-affected areas. Still troubled by the biggest SARS outbreak outside of Asia in recent months, Toronto now faces further harm to its important convention and tourism industry because of the renewed cases.
Officials worry the WHO could issue another warning against travel to the city, like one on April 23 that was lifted a week later. D'Cunha, the health commissioner, said the criteria for such a warning are 60 or more probable cases, five new probable cases a day and proof the illness was being exported to other countries.
In Athens, Greece, Prime Minister Jean Chretien told journalists the city was safe to visit.
"We had a new case that appeared last week and it was confined in the hospital section of the city of Toronto...it is under control," said Chretien, who was attending a meeting of European Union leaders. "This is a problem that is serious, but it is not dangerous at all to travel to Toronto."
The possible exposure at Father Michael McGivney Catholic Academy in Markham, a northern suburb of Toronto, involved a student who attended school last week while feeling ill, officials said. The student is the son of a health care worker linked to a Toronto-area hospital with known SARS cases and also displaying SARS-like symptoms.
On Wednesday, the student was listed as a suspected case of SARS, but Dr. Murray McQuigge, a York Region Public Health official, said there was no doubt.
"We're saying this person does have SARS. This is deadly serious business," McQuigge told a news conference. He read out guidelines for home quarantine, including no visitors, sleeping in a separate room from anyone else, and wearing a respirator mask when in contact with others. He said health authorities will deliver the masks to those in quarantine.
Health officials described the closing of the school until June 3 as a precaution, but acknowledged they still were learning about the illness from Asia that has erupted anew after the initial outbreak appeared under control.
The WHO designation of Toronto as SARS-affected is routine for places with new cases of the illness. WHO spokesman Dr. David Heymann said Wednesday the U.N. agency always knew Toronto could face a renewed outbreak, and there were no plans to re-impose a warning against travel to the city.
In response to the new cases, health authorities re-imposed strict controls on Toronto-area hospitals -- closing those where the new cases were found to new patients and limiting access to emergency rooms in all others.
Toronto had been removed from the WHO list of SARS-affected areas May 14 after more than 20 days passed without a new case being reported. The new cluster is believed to come from an elderly patient whose case dates from April 19.