The United States has now recorded more cases of measles in 2026 than in any other year since the virus was declared eliminated in 2000, a grim sign that the country may be headed toward a new era in which the disease regularly sickens thousands every year.
On Friday, the Centers for Disease Control and Prevention announced that there have been 2,318 confirmed cases of measles so far this year. The case count toppled the record set last year, when measles infected more than 2,200 Americans and killed two unvaccinated children. More measles cases have been reported in the United States in the last two years than in all the years from 2000 through 2024 combined.
Reversing course on measles would require a nationwide push to improve vaccination rates, a prospect that experts said seemed unlikely under the leadership of Health Secretary Robert F. Kennedy Jr. He has halted funding for vaccine hesitancy research, downplayed the risks of measles and spearheaded a hunt for evidence that vaccines are unsafe.
In November, a panel of international experts will meet to determine whether the United States has lost its elimination status, which has long been viewed as one of the country’s crowning public health achievements.
“This is just going to keep happening,” said Jennifer Nuzzo, director of the Pandemic Center at the Brown University School of Public Health. “It’s going to mean living in a perpetual state of vulnerability and risk until we get vaccination levels up.”
Many of the cases reported this year were tied to a large outbreak in South Carolina that took root last October in a close-knit, evangelical Slavic community and quickly became the largest outbreak in the United States since 2000. The outbreak, which ultimately sickened nearly 1,000 people, was declared over by state health officials in April.
Still, the virus is far from contained. Utah is fighting an outbreak that began along its border with Arizona last summer and has led to more than 700 cases, spread across every jurisdiction in the state. Virginia health officials have reported more than 170 cases from an outbreak that began in mid-May. Pennsylvania is grappling with an outbreak that has sickened more than 100 people this year.
In total, the C.D.C. has reported 35 new measles outbreaks this year. A vast majority of cases have been in people who were unvaccinated or whose vaccine status was unknown.
The string of outbreaks is no surprise to public health experts, who have watched vaccination rates tick down in recent years. Nationally, the measles vaccination rate fell during the Covid-19 pandemic and has not rebounded to the 95 percent required to stem the spread of the measles virus in a community. While the latest national data shows that about 93 percent of kindergartners have received the measles, mumps and rubella shot, that protection is uneven: Some communities have vaccination rates approaching 100 percent, while others have rates below 80 percent.
Measles, one of the most contagious diseases, is exceptionally good at exploiting those pockets with weak immunity.
“It’s going to find people who aren’t immune,” said Dr. David Kimberlin, a pediatric infectious disease expert at the University of Alabama at Birmingham. “It’s like a heat-seeking missile.”
Children have borne the brunt of the infections, making up more than 70 percent of confirmed cases. More than 80 children and adolescents have been hospitalized this year for complications like pneumonia, which leaves patients gasping for air, and brain swelling, which can cause lasting damage, including blindness, deafness and intellectual disabilities. (There are no treatments for measles, though researchers are trying to develop them.)
While many of the children who became ill were vulnerable to the virus because their parents opted them out of the measles vaccine, local health departments have also reported several cases in babies too young for the shot and people with health conditions that make them ineligible for the vaccine.
The outbreaks have taken a steep economic toll, as state and local public health departments strained to track down everyone exposed to the virus, start vaccination campaigns and analyze tests. Researchers have estimated that in 2025, each measles case cost the United States more than $100,000, when factoring in health care spending and the days of missed work for sick people or caretakers.
The United States is not the only country grappling with a measles resurgence. Canada, which lost its elimination status last year, has reported more than a thousand cases this year. Health officials in Bangladesh confirmed more than 8,000 infections since March.
Still, several experts said the Trump administration’s response — which has not included any national push to increase vaccination rates — has done the United States no favors.
Courtney Spencer, a spokeswoman for the Department of Health and Human Services, said the department has mounted an “aggressive outbreak response,” and pointed to the $8.5 million it has given states to help contain outbreaks and the technical assistance that the C.D.C. has provided to those areas.
She added that the department has said, referring to the vaccine against measles, mumps and rubella, that “M.M.R. vaccination remains the best protection against measles.”
Dr. Jonathan Temte, a former chairman of the C.D.C.’s vaccine advisory committee, said: “We have seen virtually no national messaging. We’ve seen no ad campaigns.” He added, “I think that really tells us something about their priorities.”
