What we learned from South Carolina’s measles outbreak

April 29, 2026

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What we learned from South Carolina’s measles outbreak

The recent measles outbreak in South Carolina sickened nearly 1,000 people before public health officials got it under control. Vaccination can effectively prevent further spread

By Tanya Lewis edited by Claire Cameron

A fact sheet for measles sits on a table at a mobile clinic offering free vaccinations on February 6, 2026, in Spartanburg, S.C.

Sean Rayford/Stringer/Getty Images

South Carolina’s measles outbreak lasted about six months and sickened nearly 1,000 people in what was the U.S.’s worst flare-up of the disease since it was declared eliminated in the country in 2000. And while officials declared that the state’s outbreak was over on Sunday, the disease still poses a danger for the U.S.

South Carolina’s outbreak primarily affected unvaccinated children in an insular religious community in Spartanburg County. Experts applaud the public health response to the outbreak but say more measles cases could be on the horizon so long as vaccination rates remain low in pockets of the U.S.

“Being able to say this outbreak is over is certainly reassuring for the state of South Carolina,” says Stephen Thacker, an associate professor of pediatrics and an infectious disease specialist at the Medical University of South Carolina. “But it doesn’t mean that measles is necessarily behind us.... Measles anywhere is a risk everywhere.” And vaccination remains the best defense against outbreaks, he adds.

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In the past two years, measles cases in the U.S. have skyrocketed, with outbreaks on a scale that had not been seen since the disease was deemed eliminated in the country a quarter-century ago. A major outbreak occurred last year in Texas, where 762 people were sickened and two children died; both were unvaccinated. The recent flare-ups—including currently active outbreaks in Utah and Florida—have come amid a steady decline in vaccination rates and rising hesitancy and antivaccine messaging from the highest levels of government. As a result, the U.S. has been on track to lose the disease’s elimination status; a meeting to determine that is scheduled for the fall.

The measles outbreak in Spartanburg was confirmed in October 2025. Infections spread rapidly through the undervaccinated community, especially among school- and daycare-aged children and their families. Twenty-one people were hospitalized with the disease, and some developed rare complications such as pneumonia and brain swelling; 874 students were quarantined and kept out of school for weeks.

The outbreak didn’t cause any deaths, but even people who have recovered from infection continue to face some risks. Measles resets the immune system, wiping out some of the immunity conferred by other vaccines. And in rare cases, the disease can cause a deadly form of brain inflammation called subacute sclerosing panencephalitis, which can develop up to 10 years after an infection. It causes progressive neurological dysfunction, coma and often death. It is “a really scary disease that, thankfully, is extremely rare. But it is something that I would never wish upon or want for anyone I know or love,” Thacker says.

Ultimately, public health workers got control of the outbreak through testing, contact tracing, isolating of sick and exposed individuals and vaccination. “That approach is really how you successfully change the tide of an outbreak,” Thacker says.

Vaccination is the most effective way to prevent and stop an outbreak. And it’s critical for protecting people who can’t get a vaccine, such as most children under the age of one or people who are immunocompromised.

Numerous studies have shown the measles, mumps and rubella (MMR) vaccine is extremely safe and effective. Two doses provide more than 97 percent protection against a measles infection, often for life. And there is no evidence the vaccine causes autism.

The measles vaccine has been the subject of a lot of misinformation and disinformation, says Martha Edwards, president of the South Carolina Chapter of the American Association of Pediatrics. “Parents have been fed this [idea that measles is] a routine childhood illness,” Edwards says. “And really none of the things we vaccinate for are routine—they’re really difficult, sometimes lethal illnesses.”

Edwards says the antivaccine views of Secretary of Health and Human Services Robert F. Kennedy, Jr., a longtime vaccine skeptic, have played a “huge role” in the recent spread of measles the U.S. &ldqu