The number of confirmed measles cases in the city is now 10 after Toronto Public Health reported a new case on Saturday.
There are now 18 confirmed cases in Ontario.
No further details on this latest case have been released and there has been no word on if this is case is linked to a Christian youth event held in Toronto earlier this month.
About 1,000 people who attended the event were warned by health officials last week that they may have been exposed to measles.
Meanwhile, health officials say a 19th case of measles has been confirmed in Quebec.
Public health officials at a news conference on Saturday would not confirm whether the new case is a child or an adult, nor whether it is linked to Quebec’s previous 18 cases.
The source of the outbreak for the first 18 cases has been traced to Disneyland, California.
All of the Quebec cases have been concentrated in the Lanaudiere region, northeast of Montreal.
None of the people infected in Quebec were vaccinated for the disease.
Quebec health authorities said that several dozen other people are currently under observation, since measles has a two-week incubation period.
Manitoba has also reported a case.
While measles was declared eliminated from the U.S. in 2000, the illness has reappeared in recent years.