The Toronto area reported two new cases of SARS today, one probable case and another suspect one, and a senior medical official said the news was a setback to Canada's efforts to declare itself SARS-free.
"For us this is a setback," Dr Donald Low, chief of microbiology at Mount Sinai Hospital in Toronto told reporters.
"It is unfortunate. We would like not to see this happen ... but we have to remember that we still have active disease in SARS units and the potential always exists that a transmission could occur."
The two new victims were nurses who treated victims of Severe Acute Respiratory Syndrome in the Toronto area, the only place outside Asia where people have died from SARS.
But Dr Low said health officials could take comfort from the fact that there have been no new cases of the flu-like illness outside hospitals in more than three weeks.
As of Wednesday, there were 346 probable and suspect cases of SARS across Canada.
The Toronto area had 262 cases as yesterday and has reported 23 deaths from the disease, which originated in southern China and has been spread through travelers.