Measles in South Carolina has spread to at least 789 people, surpassing the 2025 West Texas outbreak that sickened 762 people and killed two young girls.
The majority of cases remain centered in Spartanburg County, mostly among people who were either unvaccinated or didn't know their status, the South Carolina Department of Public Health reported Tuesday. There have been 89 new cases confirmed since Friday, a clear sign that the outbreak isn't under control.
During a media briefing Wednesday, South Carolina state epidemiologist Dr. Linda Bell said that the speed of the spread has been surprising.
“We did not anticipate that South Carolina case counts in a matter of only 16 weeks would surpass the total number of cases reached in Texas over the course of 7 months,” Bell said. “It’s disconcerting to consider what our final trajectory will look like for measles in South Carolina.”
As many as 557 people in South Carolina are in quarantine for 21 days following measles exposures.
South Carolina’s outbreak has exploded at a dizzying pace. The first cases were reported in late September and picked up steam during the holidays.
By January, cases directly linked to the state had been documented in California, North Carolina and Washington. Several other probable cases were reported in Ohio, according to NBC affiliate WKYC of Cleveland.
Dr. Zack Moore, state epidemiologist for the North Carolina Department of Health and Human Services, said he’s keeping watch on vulnerable areas in the western part of the state with low vaccination rates and geographically close to the South Carolina outbreak zone.
“We know there’s a lot of back and forth travel, so that is certainly a concern,” Moore said during a Jan. 21 media briefing.
North Carolina health officials have reported 14 cases as of Tuesday, some with direct links to South Carolina.
More than 170 people under quarantine in Union County, North Carolina, are connected to a case at Shining Light Baptist Academy, a private Christian school that has children as young as 6 weeks old.
The quarantine orders stem from an unvaccinated child who attends the school, according to a Union County Public Health alert, “and contracted measles connected to an outbreak in South Carolina. The child attended school while contagious.”
According to the North Carolina Department of Health and Human Services, just 60.1% of students at Shining Light Baptist Academy are vaccinated against measles. A vaccination rate of at least 95% is the accepted level of herd immunity needed to protect against a measles outbreak.
“If you have schools that have very low vaccination rates, you essentially create a tinder box for measles, because it is so incredibly contagious,” said Dr. Deborah Greenhouse, a past president of the South Carolina chapter of the American Academy of Pediatrics. “That’s what happened in the upstate of South Carolina, and that’s exactly what can happen over and over again if the disease spreads to other areas with low vaccination rates.”
The news was distressing to doctors working to contain the outbreak.
“I am very sad,” said Greenhouse, who is also a pediatrician in Columbia, South Carolina. “It emphasizes even more that we need to continue the work of trying to educate families in South Carolina and trying to get families to understand that the way we shut this down is by increasing our vaccination rates and by complying with isolation and quarantine.”
Most of those sickened are children and teenagers, health officials said. At least 23 schools in South Carolina have students in quarantine.
“Without better vaccination coverage to achieve herd immunity more widely, we can anticipate that many more susceptible people will contract measles in South Carolina, that we’ll continue to see spread potentially to other areas of the state,” Bell said.
Losing measles elimination status
The South Carolina milestone comes as the U.S. teeters toward losing its measles elimination status. That could occur as soon as this fall if it’s determined that the virus originated from a single source and continued to circulate for a full year.
In a call with reporters on Jan. 20, the new principal deputy director of the Centers for Disease Control and Prevention, Dr. Ralph Abraham, appeared to shrug off the matter.
“It’s just the cost of doing business, with our borders being somewhat porous,” Abraham said. “We have these communities that choose to be unvaccinated. That’s their personal freedom.”
Small communities opting out of vaccination
It’s close, tight-knit communities with the lowest vaccination rates that have been hit hardest, according to an NBC News data investigation.
South Carolina’s outbreak, health officials said, was first reported among families who immigrated from Ukraine to Spartanburg County in recent decades. The county has one of the highest percentages of nonmedical vaccine exemptions at 8.2%, meaning schoolchildren are opting out of vaccination for personal or religious reasons.
In West Texas, cases occurred mostly in a Mennonite community in Gaines County where nonmedical vaccine exemptions are at 19.5%.
The outbreak concentrated along the border of Arizona and Utah is mostly linked to residents with ties to the Fundamentalist Church of Jesus Christ of Latter-day Saints. Mohave County, Arizona’s nonmedical vaccine exemptions are at 15.9%, and neighboring Washington County, Utah, is at 19.6%.
While Abraham acknowledged that the measles-mumps-rubella vaccine is “effective,” he did not explicitly encourage vaccination in outbreak areas.
In 2025, the U.S. recorded more measles cases than in any year since 1991: 2,255, according to the CDC. So far in January, 416 cases have been confirmed nationwide.
The vast majority (93%) of patients have been unvaccinated.
