Canada has officially lost its measles elimination status, marking a major setback for public health authorities after vaccination rates fell below the critical threshold needed to prevent transmission. The World Health Organization (WHO) confirmed the downgrade on Monday, citing ongoing outbreaks that have spread across provinces and linked to rising cases in the United States and South America.
The country, which achieved measles-free certification in 2016, has now joined a growing list of nations where vaccine hesitancy, misinformation, and pandemic-era healthcare disruptions have allowed the highly contagious virus to regain a foothold.
“We’re seeing the direct consequences of falling immunization coverage,” said Dr. Theresa Tam, Canada’s Chief Public Health Officer. “Once measles re-enters a community, it spreads faster than almost any other virus we know.”
The Numbers Behind the Reversal
National data shows Canada’s childhood measles vaccination rate has slipped to 91.7%, well below the 95% herd immunity threshold required to halt community spread. That small gap has proven devastating: over 2,400 confirmed cases have been reported this year, with clusters in Ontario, British Columbia, and Quebec.
At least four deaths and 36 hospitalizations have been linked to complications from the virus, according to the Public Health Agency of Canada (PHAC).
“Every percentage point lost means thousands more children at risk,” said Dr. Isaac Bogoch, an infectious disease specialist at the University of Toronto. “This is not a failure of medicine; it’s a failure of communication.”
Global Patterns of Regression
The resurgence is part of a regional pattern of backsliding across the Americas. Earlier this year, Argentina and Brazil
