- Measles cases in the U.S. surged in 2025 with over 2,200 confirmed cases.
- Texas, South Carolina and Utah-Arizona border experienced significant outbreaks, risking elimination status.
- Experts cite low vaccination rates as a key factor, urging improved coverage efforts.
DALLAS — Tuesday marks one year since a measles outbreak started in west Texas, and there have been new cases in the United States each week since.
Texas reported more than 760 cases — and the deaths of two children – before declaring the outbreak over in August. It was the largest outbreak the US had seen in decades, and since then, other large outbreaks — one in the upstate region of South Carolina and another on the border of Utah and Arizona — have amassed hundreds of cases each and continue to expand.
The first two weeks of 2026 have been some of the worst yet, with exposures reported at schools, churches, restaurants, shops, airports and more. The continuous spread of measles over the past year leaves the US at risk of losing elimination status, which the country has held since 2000.
"It is startling, because just a few years ago, measles was very rare in the United States," said Dr. Caitlin Rivers, an epidemiologist and director of the Center for Outbreak Response Innovation at the Johns Hopkins Bloomberg School of Public Health.
"Now we're seeing in a single week what we might have seen in an average year," she said. "There's been a real shift in the presence of this preventable disease in our life."
Whether that balance can shift back depends on how quickly the US can improve vaccination coverage, experts say – which, in many ways, has become an uphill battle.
The US reported more than 2,200 confirmed measles cases in 2025 — significantly more than there have been in any year since measles was declared eliminated in the US in 2000. At least 171 measles cases have been reported in the first two weeks of 2026, which is nearly as many as the average annual total in those 25 years since elimination in the US.
The vast majority of cases — more than 95% — have been in people who had not been vaccinated with the recommended two doses of the measles-mumps-rubella (MMR) vaccine.
Experts fear that the situation may have to get much worse before it gets better.
It's particularly devastating, they say, because the illnesses and deaths they foresee are almost entirely preventable with the help of vaccines — but lagging coverage has left many vulnerable.
It's not clear yet whether the US will maintain its measles elimination status. In April, the Pan American Health Organization, part of the World Health Organization, will formally make the determination. The decision will require a detailed review of epidemiological and laboratory evidence to understand patterns of measles spread over the past year — including whether more recent outbreaks are linked to the Texas outbreak.
But experts say that formally losing measles elimination status would be a symptom of more deeply rooted issues, particularly challenges with vaccination that have been building for many years.
"Let's face it, whether we lose elimination status or not in spring, is our public health system actually doing well?" said Dr. Demetre Daskalakis, former director of the US Centers for Disease Control and Prevention's National Center for Immunization and Respiratory Diseases, who resigned in protest last year.
"Measles elimination is a vital sign of our public health system. That public health system is blue in the ICU," he said. "I don't need to check its pulse to know [it's not doing well]. I know the answer."
A record share of U.S. kindergartners had an exemption for a required vaccination last school year, according to data from the CDC, marking the fifth year in a row that coverage with the MMR vaccine was below the federal target of 95%.
The CDC says that the increase in vaccine exemptions may be "due to an increase in vaccine hesitancy." A recent survey of parents conducted by the agency found that most supported vaccine requirements to attend school. But among those seeking an exemption, the most commonly reported reason – cited more than a third of the time – was a philosophical or personal belief objection to vaccination. Difficulty meeting school requirements by the deadline was also reported as a reason for exemption by about 23% of parents. Medical reasons were cited by more than a quarter of parents, but the CDC said that might include parents who consider concerns about vaccine safety or side effects as a "medical" reason to request an exemption.
"Vaccines are a victim of their own success. It's not just that we eliminated measles. I think we eliminated the memory of measles," said Dr. Paul Offit, director of the Vaccine Education Center at the Children's Hospital of Philadelphia.
Offit remembers speaking with Dr. Maurice Hilleman, a microbiologist who developed the MMR vaccine and dozens of others, just months before Hilleman's death in 2005. Measles cases had reached a record low in 2004 but were starting to trend up again, just a few years after the US had achieved elimination following a long and hard-fought battle.
"I asked him, 'Do you think that we can educate people about the importance of the vaccine, about the serious nature of this disease, or does the virus have to come back?" Offit said. He said there was a tear in his eye when he replied that the virus was going to have to come back to teach that lesson.
"That was an enormous defeat for him," Offit said. "It's an enormous defeat for us to once again see children be exposed to something that could kill them — and did kill them – in this country, when that was completely unnecessary."
But it seems more and more that the virus isn't necessarily doing that, educating either, Offit said.
There were three deaths from measles last year — as many as there had been over the past 25 years combined — yet it's been a struggle to increase vaccination rates, even in communities that experienced outbreaks.
The South Carolina health department has offered a mobile vaccination clinic since the early weeks of the outbreak in the upstate region of the state, but state epidemiologist Dr. Linda Bell has said that uptake has been "disappointing."
Measles outbreaks tend to occur in under-vaccinated pockets of the U.S., often in tight-knit communities, such as those with certain religious beliefs.
