International health authorities plan to assess whether the United States has lost its measles elimination status, a decision scheduled for April 13, according to the Associated Press. The review is expected to take place amid renewed measles transmission across multiple states following a large outbreak in West Texas last year.
The reassessment is described as largely symbolic, with experts saying it turns on whether investigators determine that a single chain of measles spread uninterrupted within the U.S. for at least 12 months. The investigation also includes work to determine whether the ended Texas outbreak is linked to active cases in Utah, Arizona and South Carolina.
Dr. Jonathan Temte, a Wisconsin family physician who helped certify the U.S. was measles-free in 2000, said the debate is largely a matter of wording. “It is really a question of semantics,” Temte said. He added that “The bottom line is the conditions are sufficient to allow this many cases to occur,” and said the situation ties back to “de-emphasizing a safe and effective vaccine.”
The CDC confirmed 2,242 measles cases across 44 states in 2025, the most since 1991, and nearly 50 separate outbreaks, the AP reported. Researchers and public health specialists attributed the resurgence to several factors, including fewer routine vaccines in some communities due to parental waivers, health care access issues, and disinformation.
Brown University’s Pandemic Center director Jennifer Nuzzo said the focus should remain on vaccination coverage. “The most important thing that we can do is to make sure the people who aren’t vaccinated get vaccinated,” she said, adding, “We have not issued a clear enough message about that.”
In a statement to the AP, a spokesperson for the U.S. Department of Health and Human Services said Robert F. Kennedy Jr. has emphasized vaccines as the best way to prevent measles, and that the CDC is responding to outbreaks and working to increase vaccination rates. In a Tuesday briefing, department officials said they do not yet have evidence that a single chain of measles has spread for a year.
CDC’s principal deputy director said he would consider any loss of elimination status to be the “cost of doing business” globally. Dr. Ralph Abraham said communities that choose not to vaccinate are exercising “personal freedom,” according to the AP.
Measles is among the most contagious infectious diseases, and the AP reported that it infects 9 out of every 10 unvaccinated people exposed. Community-level protection is associated with a 95% vaccination rate, while CDC data cited by the AP places the national vaccination rate at 92.5%, noting that some communities are far below that level.
In Texas, state health department data says the first known case developed the telltale rash on Jan. 20, 2025. The outbreak later officially involved 762 people, most of them in rural Gaines County, and two children died. State health officials said 182 potential measles cases among children in Gaines County went unconfirmed in March 2025 alone, a possible undercount of 44% in that county.
The AP reported that such gaps can complicate outbreak tracking, particularly when people in affected communities face barriers including limited access to health care and distrust of government. Behavioral scientist Noel Brewer, who chairs a U.S. committee that will finalize data for international officials, said tracing many cases is expensive, and that research shows one measles case can cost public health departments tens of thousands of dollars. Brewer also said the U.S. has changed its investment in public health and is less able to do the case tracking it used to do.
Genetic sequencing has offered some clues, but it may not resolve whether outbreaks share continuous transmission. Sebastian Oliel, a spokesperson for the Pan American Health Organization, said scientists confirmed the same measles strain in Texas, New Mexico, Utah, Arizona, South Carolina, Canada, Mexico and several other North American countries. Justin Lessler, a University of North Carolina disease researcher, said that “Within an outbreak, everybody is going to look the same,” which can make it harder to connect separate outbreaks using genetic information alone.
Dr. Andrew Pavia, a Utah physician and longtime CDC consultant, said his best guess is that the U.S. will lose elimination status. “My best guess is we will lose elimination status,” Pavia said, describing the case for uninterrupted transmission as “tenuous.” Pavia also said investigators may err on the side of declaring a loss of elimination status.
Oliel said PAHO will make the final decision on U.S. measles elimination at an April 13 meeting. He also said PAHO plans to review Mexico’s measles-free status alongside the U.S. and that Mexico’s largest outbreak has roots in Texas, with the AP reporting that it began after an 8-year-old boy from Chihuahua state got sick following a visit to family in Seminole, Texas.
The AP reported that measles has spread in the U.S. in 2025, including in schools and day cares, churches, hospital waiting rooms and a detention center. In the three-state area at the center of ongoing concern, it said more than 800 people have gotten sick across Utah, Arizona and South Carolina since late summer, with no end in sight. Noel Brewer said: “2025 was the year of measles,” adding that it was still unclear whether 2026 would bring rising or falling case counts.