A flight attendant arrives at Pearson International Airport from Mexico City wearing a mask as a precaution against contracting swine flu. (Nathan Denette/Canadian Press)

Toronto's chief medical officer of health said Tuesday morning there are no reported cases of swine flu in the city, but that they would likely appear "in the near future."

"To date no cases of swine flu have been reported in Toronto — or elsewhere in Ontario — however, in view of the volume of travel within North America and the ease of transmission of influenza it's very likely the cases of swine flu infection will occur in Toronto in the near future," Dr. David McKeown told a news conference at Toronto City Hall.

Mayor David Miller emphasized there are "no cases [of swine flu] in the city" but at the same time the city's public health department is taking steps to "be prepared and ready," he said.

Miller said the city has been in constant contact with other municipalities, the province and health-care providers to ensure that any cases that might be swine flu are reported quickly.

Health bulletins have been distributed asking doctors to report patients who exhibit signs of influenza if they have travelled to parts of Mexico or the United States where there have been infections.

"We appreciate that there is uncertainty about the spread of swine flu. We will continue to keep Torontonians informed as to any steps that we need to take should they be needed," said Miller.

On Monday, Ontario's associate medical officer of health, Dr. David Williams, said there were about 12 people in the province with severe respiratory illnesses who had travelled to Mexico, but so far there are no confirmed cases.

Williams also said the province has a large supply of antiviral medication — enough to treat 25 per cent of the population.

Anyone who suspects they may have swine flu is being asked to telephone their doctor, their local public health unit or Telehealth Ontario at 1-866-797-000.

The province also has an information line in operation for people who have questions about swine flu. They are asked to call Service Ontario at 1-800-476-9707, TTY 1-800-387-5559.

Information is also available at the City of Toronto website.