Google Street View A measles outbreak has been linked to École Jules-Verne school in Vancouver, seen in this undated photo. (Credit: Google Street View)

Vancouver Coastal Health says it's facing an "outbreak" of measles with nine cases in the city this month.

The number of confirmed cases more than doubled from four earlier on Friday, when the health authority said all the infections involved three French schools.

Two of the schools are connected by a door and the schools use the same bus company.

Medical health officer Dr. Althea Hayden says most of the new confirmed cases are linked to École Jules-Verne, a French-language high school in South Vancouver, reported CBC News.

"We now have an outbreak," said Hayden. "Cases are occurring in staff, students and family members affiliated with this school."

Urging people to get vaccinated

She defined an "outbreak" as a number of cases that are higher than expected; Vancouver should have zero cases if immunization levels were adequate, she said.

Hayden says many of the people exposed have already been vaccinated, but she's asking anyone who may be at risk to get checked out.

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