Why are measles case counts climbing so high in Alberta? Experts weigh in

Infectious disease experts are raising the alarm about measles spread in Alberta, warning case counts are far higher than neighbouring provinces and they’re increasing rapidly.

Alberta reported 116 more measles cases last week, pushing Alberta’s total of confirmed cases to 326 as of Friday. 

“[It’s] really the largest growth in the number of cases of measles — at least per capita — of any place in Canada,” said Craig Jenne, professor of microbiology, immunology and infectious diseases at the University of Calgary.

“It’s going to be very difficult to rein this in.”

Alberta’s case counts are second only to Ontario, which has reported more than 1,400 cases since its outbreaks began in October.

That province, which has three times the population, recorded 197 new cases in its latest weekly update.

Neighbouring provinces are not nearly as hard hit.

As of Friday, British Columbia had reported eight cases and Saskatchewan’s tally sat at 27.

“We are almost at a tipping point where either we bring everything to the table and put some resources into trying to contain this or we might see numbers going up towards what we are seeing in Ontario,” said Dr. Lynora Saxinger, an infectious diseases specialist at the University of Alberta.

Alberta’s south zone is the hardest hit with 200 cases as of Friday. The central zone had reported 86 cases by the end of the week.

Why is Alberta so hard hit?

“The single most predominant determinant of whether measles spreads is vaccine status,” said Jenne.

“Alberta is typically below most other jurisdictions. And there are regions of Alberta that are significantly below the other provinces, and these really provide the tinder for these growing fires of infectious disease.”

According to the Alberta government website, two doses of the measles vaccine offers nearly 100 per cent protection.

Provincial data shows 71.6 per cent of seven-year-olds were up-to-date with both doses of the vaccine in 2024. 

That’s far below the 95 per cent threshold experts say is needed for population-level protection.

Next door in Saskatchewan, vaccination rates are higher.

According to the Saskatchewan Ministry of Health, 87.4 per cent of seven-year-olds in that province were fully vaccinated with two doses of the measles vaccine in 2024.