As part of its evaluation, PAHO reviewed epidemiological and laboratory evidence submitted by the US Centers for Disease Control and Prevention to determine whether the same strain of measles had been circulating in the United States uninterrupted for 12 months or longer, a sign of local transmission rather than imported cases.
Canada, Spain and the UK recently lost measles-elimination status after review by WHO experts. The US dropped out of WHO but remains a member of PAHO, its Americas branch.
Dr Erica Schwartz, director of the US Centers for Disease Control and Prevention, told Reuters in an interview before the decision that if the US lost measles elimination, the agency would be doing “the same exact thing,” which entails working with states to encourage immunisation.
As of Thursday, 5,182 confirmed cases of measles had been reported in 2026 to the US Centers for Disease Control and Prevention from 45 states, New York City and the District of Columbia, surpassing last year’s total of 2,289, making it one of the country’s worst measles resurgences in decades.
“It is a fully preventable disease. It is unconscionable that we have this amount of measles,” said Noel Brewer, a public health professor at the University of North Carolina.
Brewer, who chairs an independent advisory panel on measles, presented the CDC’s measles status report along with his group’s assessment of that information to PAHO on Tuesday.
