How one public health unit is tackling Ontario’s biggest measles outbreak in decades [Video]

For the second time in five years, some doctors in southwestern Ontario are encountering a virus they’ve never treated before.

But unlike when COVID-19 struck in 2020, this illness is no mystery.

It’s understood so well, in fact, that Canada was able to eliminate it in 1998. Anyone in Ontario who got their medical degree after that is unlikely to have seen measles up close, said Dr. Ninh Tran, medical officer of health for the Southwestern Public Health Unit, where 89 people have come down with the virus since the beginning of 2025.

That’s why measles wasn’t top of mind when last fall people started coming down with respiratory symptoms, nausea and a red, blotchy rash.

“The seriousness of measles, the number of cases, what infection really looks like, the complications, the hospitalizations: People forget if you haven’t seen it around for decades.”

In Tran’s mostly rural region outside London …