One of the doctors who led Toronto's battle against severe acute respiratory syndrome (SARS) said on Thursday that the virus was still lingering in hospitals of Canada's largest city, but the outbreak was nearly over.
"Clearly, the outbreak as we know it is behind us," Dr. Donald Low, chief of microbiology at Mount Sinai Hospital, told reporters. "We have people in hospitals who are sick. They pose a threat not to the community but to health workers who are looking after them."
There have been 327 probable and suspect cases of SARS in Canada, including 263 in the area around Toronto, Canada's financial hub. But only 42 people are still in hospital, down from 69 people 10 days ago.
Four of them are in critical condition.
Twenty three people have died from the disease in Ontario, the only place outside Asia where people have died from SARS.
The disease originated in China and has killed more than 500 and infected more than 7,300 people. More than half the cases and 220 of the deaths have been in China.
Toronto-area hospitals are still shut to visitors as a precaution against infection, and staff dealing with SARS patients wear double layers of gloves, full face shields, masks and goggles.
"It would be premature to declare us disease free just two weeks after the last case," Low said, adding that the World Health Organization (WHO) requires no new cases for 20 days after the last one is reported to declare an area SARS free.
The WHO last month advised travelers to avoid Toronto but lifted the recommendation after a week when Canada provided new data and promised to step up screening at Toronto airport to ensure that people with high fevers -- a SARS symptom -- did not board planes and spread the disease.
"I do not think we are going to see them [the WHO] declaring Toronto a disease free area [soon]," Low said. "With the number of cases we still have that are considered active within the hospitals, I would not expect to see that happen."
Low said the last SARS cases contracted in Canada were medical workers who fell ill on April 18. A woman returning from a trip to Asia in late April is also under investigation after she displayed SARS-like symptoms.
When it issued its Toronto travel advisory, the WHO said it was concerned Canada was exporting cases to other countries.
"Toronto is almost in a kind of no-win situation," Low said, noting that the US Centers for Disease Control defines a SARS case as somebody who has a lower respiratory tract infection and fever who comes from an infected area.
Under that definition, five SARS cases reported in the US in the past month have come from Toronto.
"To me those are non-cases because we have no disease in the community," Low said, pointing out that out of thousands of people leaving Toronto for the US, five coming down with pneumonia would have not been a cause of worry before.
"Now because (these cases) come from Toronto they are automatically called SARS," Low said. "It perpetuates this myth that we are exporting the disease, and we have not had disease in the community since April 10."
A spokesman for Health Canada, the federal ministry responsible for health issues, could give no timeline for when Canada would declare the SARS outbreak over.
"We still remain vigilant and prudent," he said.