04/02/2014 06:47 EDT | Updated 06/02/2014 05:59 EDT

Calgary Measles Cases Grow By 2

BSIP via Getty Images
Reportage in the Health and Prevention Centre run by the local committee for social hygiene (CDHS) in Lyon, France. MMR vaccination. Priorix immunises against measles, mumps and rubella. (Photo by: BSIP/UIG via Getty Images)
CALGARY - Alberta Health Services has confirmed two new cases of measles in the Calgary zone.

Officials say the cases are linked and involved multiple exposure settings including a Calgary area high school.

A letter has been sent to staff and students at Western Canada High School, which was posted to the school’s website on Wednesday.

AHS will release more details on the new cases Thursday.

This now makes six confirmed cases in Calgary this year; there have been only 20 in the past 13 years.

Measles starts out with a fever, and a rash develops three to seven days later.

The problem, say officials, is that a person is considered infectious the day before the fever hits.

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