Canada Just Lost Its Measles-Free Status. The U.S. Could Soon Follow

Canada has just lost its status as a measles-free country. The United States could soon follow

By Humberto Basilio edited by Tanya Lewis

Canada has lost its measles-free status after a year of continued measles transmission, the Pan American Health Organization (PAHO) announced today. As a result, the entire Americas region is no longer measles-free.

The Americas became the first region in the world to be declared free of the disease in 2016, following a 22-year regional campaign that relied on mass vaccination against measles, mumps and rubella.

“This loss represents a setback, but it is also reversible,” PAHO Director Jarbas Barbosa said in a press briefing today.

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So far this year, Canada has confirmed 5,162 cases of measles. In response to PAHO’s statement, the Public Health Agency of Canada said in a statement that it was working with PAHO and federal and local authorities to improve vaccination coverage, strengthen data sharing, improve surveillance and provide evidence-based guidance.

“Canada will be able to restore its measles elimination status once transmission of the strain linked to the current outbreak has been interrupted for at least 12 months,” the agency’s statement said.

In addition to Canada, active measles outbreaks are currently underway in Belize, Bolivia, Brazil, Mexico, Paraguay and the United States. Health experts have warned that the United States has been on shaky ground since an outbreak of 762 cases that began in West Texas in late January 2025; this outbreak was declared over on August 18.

In 2025, the United States recorded 1,681 cases of measles, the majority of which were detected in Texas, Arizona and New Mexico. Health officials are currently investigating other ongoing outbreaks in South Carolina and Utah. If these illnesses are found to be linked to the outbreak that began in late January, the United States could lose its status as a measles-free state for the first time in 25 years.

This is not the first time the Americas has lost its measles elimination status. In 2018 and 2019, Venezuela and Brazil respectively temporarily lost their elimination status following major outbreaks. The region regained its designation as a measles-free country in 2024, so far.

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