Three new cases of measles have been confirmed in Ontario, health officials said Saturday.

A 14-year-old girl has been confirmed as the second case of measles in the Niagara Region and two adults have been confirmed as the ninth case in the Greater Toronto Area. None of them have been identified.

Lenore Bromley, media relations manager for Toronto Public Health, says one of the adults in Toronto has been diagnosed with the virus after laboratory testing — bringing the total number of measles cases in Ontario to 11.

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Bromley says the adult had no recent travel history, and their vaccine history is unknown, but there was no immediate information provided on the travel or vaccine history of the second adult.

Previous cases in Toronto include two children under two years of age and five adults, all from separate families with no recent travel history. There was also one confirmed case in the Greater Toronto Area of a vaccinated adult.

Meanwhile, Dr. Valerie Jaeger, Medical Officer of Health for Niagara Region, says the girl was confirmed as being infected with the virus after laboratory testing on Friday.

"We have identified a link to our first confirmed case," she said, adding the girl was not vaccinated against the virus.

Niagara's first confirmed case of measles was announced earlier this month as a woman in her early 20s who was also not vaccinated against the virus.

Jaeger added the Public Health Ontario laboratory has confirmed the strain of the first confirmed case in Niagara is consistent with the case announced in Niagara Region on Saturday, but due to privacy concerns would not say which municipality the latest patient lived in.

Jaeger says there is no indication the latest patient travelled outside of the country but said the patient in the first confirmed case in Niagara had travelled to Toronto.

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"Now we have evidence of transmission in Niagara so we have a heightened awareness to identify other cases of measles. That need for heightened awareness has been communicated to all primary care practitioners and emergency rooms," she said.

None of the patients in Ontario had recently travelled outside the country, which means they contracted the virus in Canada.

Health officials in Quebec confirmed on Wednesday that 10 individuals in the Lanaudiere region northeast of Montreal had been infected with measles in an event linked to the outbreak in the Disneyland theme parks in California.

On Tuesday, the Manitoba government reported the province's first case of measles of the year, but stressed it appeared to be an isolated incident.

The case involved a Winnipeg infant under 12 months old — the age the measles vaccine is typically given — who had recently returned from India.

Jaeger says the latest case in Niagara is not linked to the growing outbreak in the United States and is not consistent with the 10 cases identified in Quebec.

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She says any susceptible children who have not received two doses of measles vaccine and who have been identified as a contact of a confirmed or suspected case will be excluded from school until Public Health has been notified they received their vaccine or that the risk of exposure or illness has subsided.

Jaeger says local vaccination clinics have been busy and are prepared, and she wants parents to be aware the vaccine is safe and effective and that people should check their own and their children's vaccination records.