The warning is inspired by the discovery of a man infected with measles after he returned from a trip to the Mexico beach resort of Playa del Carmen.
Earlier, New Brunswick officials reported a case of measles in a provincial resident who had travelled to the same Mexican beach town.
The Toronto man was in Mexico in mid-February.
Dr. Lisa Berger, an associate medical officer of health, says Toronto Public Health wanted to raise measles awareness among health-care providers.
While the virus no longer circulates in Canada, Canadians who are not protected from measles by vaccination or previous infection can pick it up while travelling in places where measles still spread.
"In individuals it can be very serious, and it's highly contagious. And we'd like to prevent any spread or secondary transmission of any cases," Berger says.
Although measles doesn't spread regularly in Canada, imported cases can sometimes result in some spread. And on occasion, imported cases have sparked large outbreaks. in 2011, 750 measles cases were reported in Canada. Most of those cases stemmed from a large outbreak in Quebec.
The recommended two doses of measles vaccine gives about 99 per cent protection against the virus. Berger says people should take the opportunity to review their vaccination status and the vaccination status of their children before travelling outside the country.
Symptoms of infection include fever, a cough, red and watery eyes, a runny nose, and a rash. The rash normally starts on the face and spreads to the rest of the body. While most people recover without complications, the Public Health Agency of Canada says between two or three cases out of 1,000 result in death.
Measles infection can make a person sick for up to 10 days, Berger says. It takes on average about 10 days for symptoms to start after exposure to the virus, though that period can range from seven to 18 days.
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