Canada loses measles elimination status after three decades

"This loss represents a setback now, but it is also reversible."

Belize, Bolivia, Brazil, Mexico, Paraguay and the United States are also facing active outbreaks.

To be considered measles-free, a country must stop the spread of the virus and be free of locally transmitted cases of the same strain for 12 months or more.

Measles is a highly preventable disease when countries attain a 95% vaccination coverage rate.

That is the level needed for a community to protect those who are unable to receive the vaccine, which is 97% effective after two doses.

Health experts warn that the spread signals a looming resurgence of other vaccine-preventable diseases amid growing mistrust of vaccines since the COVID-19 pandemic.

Isaac Bogoch, an infectious disease specialist, says the government should make vaccines more accessible.

"I think it's really going to involve funding federal, provincial, and municipal public health programs so they could do the good work that they're intended to do. And part of that good work is community outreach, building trust among all the communities for which they serve, and being able to lower barriers to vaccinations, like routine childhood immunization, such that you bring the vaccines to the people rather than the people to the vaccines."

The United States and Mexico have had significant measles outbreaks this year.

Measles vaccination rates in the U.S. among kindergartners have been on the decline, according to government data.