The Pan American Health Organization (PAHO) has revoked the United States' status as a country that has eliminated measles, ending a record of control that had been maintained since 2000 for the highly contagious disease.
The US has faced a resurgence of measles over the past two years, reaching levels not seen in decades. The Centers for Disease Control and Prevention (CDC) has reported more than 5,400 cases year-to-date, far exceeding the typical annual totals of only dozens seen over most of the past 30 years. In November, five deaths were recorded across Pennsylvania, New York, and Wisconsin.
To regain elimination status, the US would need to demonstrate at least 12 consecutive months without sustained transmission, a benchmark that is expected to take years to reach.
The acceleration of the outbreak has been linked to policy shifts during the tenure of Health Secretary Robert F. Kennedy Jr., including moves to reduce childhood vaccination programs, the promotion of claims connecting vaccines to autism, and cuts to federal vaccine research funding. The CDC has also departed from long-standing immunization guidance by supporting the separation of the combined MMR vaccine into individual shots.
Measles vaccination coverage among kindergarten students has continued to slide. MMR uptake fell from 95.2% six years ago to 92.4% in the most recent school year—below the 95% threshold generally required to prevent sustained transmission.
An independent committee chair, Noel Brewer, said uncontrolled outbreaks and preventable deaths stem from low vaccination rates. Former CDC official Walter Orenstein, who previously led the 2000 elimination effort, said restoring elimination status would be extremely difficult under the current political climate.
Similar setbacks have also occurred elsewhere in the region and beyond. Canada lost measles elimination status last year, and parts of Europe have lost the status this year. Brazil, which lost its status in 2019, regained measles elimination status in 2024 after boosting vaccination coverage nationwide.
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