TORONTO - Health authorities in Canada's biggest city scrambled yesterday to explain possible new SARS cases at one hospital and how a recent visitor from the United States came down with the illness after returning home.
The 12 patients showing symptoms of severe acute respiratory syndrome at a hospital outside Toronto and the American under quarantine for SARS at his home near Raleigh, N.C., renewed fears that the World Health Organization could impose another travel warning for the city.
At a WHO meeting in Geneva, public health specialists discussed a Toronto travel warning, among other topics, but decided not to impose a new one, said agency spokesman Iain Simpson.
Toronto has been the epicenter of the biggest SARS outbreak outside of Asia, with 33 deaths reported so far. Officials reported 64 probable active cases in the Toronto area yesterday, down two from the previous day.
Twelve patients at Lakeridge Health Center in Whitby, Ontario, 40 miles east of Toronto, were under investigation for SARS symptoms. The list initially included 15 people, but three were ruled out as possible SARS patients yesterday.
"Alternative diagnoses were obtained," said Dr. Donna Reynolds, a regional health official. "The three that were removed did not have an infectious communicable cause of their illness."
Some of the remaining 12 were dialysis patients, and all had pneumonia-like symptoms consistent with SARS, but officials said it was too soon to confirm the cause of the illness.
"We have to assume they may be SARS," said Dr. James Young, the Ontario commissioner of public safety.
Authorities ordered anyone who came into contact with the patients to be quarantined at home for 10 days.
Dr. Donald Low, a Toronto microbiologist and key figure in the city's SARS containment team, said the nature of the new cluster made SARS the likely cause.
"This is very typical of a SARS outbreak, seeing a large number of pneumonia cases appear in a very short period of time," Low said. "Our experience would be that we could expect to see another 20 or 30 cases over the next week."
In North Carolina, health authorities confirmed Monday that a man developed SARS after returning from a visit last month to Toronto. He is under quarantine with members of his family, none of whom have shown symptoms, in Orange County, outside Raleigh.
The man visited a Toronto hospital patient sharing a room with people who later came down with SARS, officials said. His case raised the possibility of SARS spreading from people carrying the virus but not showing any symptoms. Until now, health authorities have worked under the assumption that only symptomatic patients spread the illness.
SARS appeared in Toronto in early March, and the initial cluster was thought to be contained by early May. Then a second cluster emerged involving an undiagnosed case at North York General Hospital that led to a further spread among patients, their relatives and health care workers.
Health care workers have complained that authorities dropped their vigilance in May in a rush to proclaim Toronto safe after the initial outbreak of SARS.
Ontario Premier Ernie Eves announced yesterday that a former judge would conduct an independent investigation of how the province and city handled SARS.
Nursing organizations have called for a formal inquiry and protection for workers who criticize their employers. While the investigation he announced falls short of that, Eves said anyone disclosing information would be protected from retribution.