The U.S. is currently experiencing its worst measles outbreak in over 30 years—and the year isn’t even over yet.
As of Wednesday, the CDC has confirmed 1,288 measles cases nationwide, surpassing the 2019 total and marking the highest count since 1992. Public health experts warn that the real number may be even higher due to underreporting.
This year’s case count exceeds the 1,274 reported in 2019, the year the U.S. nearly lost its designation of having eliminated measles—a status threatened again now if the virus keeps circulating uninterrupted for 12 months. Still, it remains far below 1991, when 9,643 cases were reported.
In response, the CDC reiterated its guidance that the MMR (measles, mumps, and rubella) vaccine is the most effective way to prevent measles, while noting it’s actively supporting outbreak response in affected areas. CDC teams have deployed twice to Texas and have also provided on-the-ground assistance in New Mexico and Kansas.
Fourteen states are currently battling active outbreaks. Four others have recently brought theirs under control. The largest outbreak, now five months long, began in undervaccinated communities in West Texas. So far, three people have died—two children in Texas and an adult in New Mexico—and dozens have required hospitalization across the country.
There are signs the outbreak may be slowing, at least in parts of Texas. Lubbock County, which treated many of the most severe cases, hasn’t reported a new infection in 50 days, according to local health director Katherine Wells.
“What worried me early in this outbreak was whether it would spread to other parts of the U.S.,” Wells said. “And it definitely has.”
Measles was declared eliminated from the U.S. in 2000, a milestone reached through decades of public health efforts. But as Dr. Jonathan Temte, a Wisconsin family physician who helped certify that status, points out, the closer a disease gets to eradication, the harder it becomes to fully eliminate.
“It’s frustrating to watch record cases emerge when we have a highly effective vaccine,” Temte said. The MMR vaccine is 97% effective after two doses and is considered safe and critical for preventing outbreaks.
Still, vaccine hesitancy remains a serious concern. A recent analysis found that childhood measles vaccination rates dropped in nearly 80% of U.S. counties after the COVID-19 pandemic, including in many states now facing active outbreaks. CDC data also shows only 92.7% of kindergartners were vaccinated in the 2023–2024 school year—below the 95% threshold needed for community protection.
Funding shortfalls haven’t helped. For years, local public health departments have seen little to no increase in support for vaccination programs. While Wells said she regularly communicates with public health officials across the country on outbreak preparedness, she also emphasized the urgent need for more resources.
“What we’re seeing with measles is kind of a canary in the coal mine,” said Lauren Gardner, who leads Johns Hopkins University’s independent tracking projects for measles and COVID-19. “It signals a deeper, growing problem with vaccine attitudes in this country—and likely one that will get worse.”
Elsewhere in North America, major measles outbreaks are unfolding: 2,966 cases in Chihuahua, Mexico; 2,223 in Ontario, Canada; and 1,246 in Alberta, Canada. These outbreaks, like the one in Texas, are connected to large Mennonite communities. While Mennonite churches don’t officially oppose vaccines, more conservative groups within the communities have historically had low vaccination rates and often mistrust government programs.
Back in 2019, the CDC recorded 22 measles outbreaks, with the largest in two New York clusters—702 cases in New York City and 412 in the state—both linked to tight-knit Orthodox Jewish communities.
