Measles surges back in the Carolinas, prompting CDC to deploy ‘disease detectives’

At Lyman Elementary School outside Spartanburg, South Carolina, the hallways have gone quiet again. Dozens of students are at home on quarantine orders. Others never came back after winter break, held out of class because their parents refused a common childhood vaccine.

This time the disruption is not from a new coronavirus variant or a hurricane. It is measles — a virus the United States declared eliminated in 2000 — and it has returned to South Carolina on a scale not seen in more than three decades.

Since last fall, health officials say, nearly 1,000 people in South Carolina have been infected, the vast majority of them unvaccinated children in and around Spartanburg County. The outbreak has spilled across the state line into North Carolina, which has confirmed two dozen cases since December and is bracing for more.

On March 9, the Centers for Disease Control and Prevention publicly escalated its response, announcing it was “reinforcing” the national measles effort by working closely with both states and deploying its Epidemic Intelligence Service — the agency’s “disease detectives” — to the region.

“Trust is the foundation of public health, earned through openness, honesty, and guided by the best available evidence,” acting CDC Director Jay Bhattacharya said in a statement announcing the move. He said the agency would “listen to our state and local partners” and offer “a wide range of tools, including vaccine supplies” to help contain the outbreaks.

The deployments illustrate how quickly a long-controlled virus can regain a foothold when vaccination coverage slips — and how much work it takes to push it back.

Biggest outbreak in decades

South Carolina’s Department of Public Health first declared a measles outbreak in the state’s Upstate region on Oct. 2, 2025, after eight unvaccinated residents tested positive. All lived in or near Spartanburg County.

In the months that followed, the case count climbed steadily. By Jan. 9, state officials reported 310 cases linked to the outbreak, most of them children and teenagers. By early February, the total had reached at least 876 and then 933 as infections spread beyond Spartanburg into Sumter and Lancaster counties. On March 10, state and local reports put the tally at about 993 cases — making it, by all accounts, the largest single measles outbreak in the United States since 2000.

At one point, about 95% of the cases were in Spartanburg County. Exposure notices went out for elementary and middle schools, big-box stores, fitness centers and a post office in communities such as Boiling Springs, Duncan, Greer and Gaffney.

Among an early subset of 111 cases in the Upstate region, 105 patients were unvaccinated, according to state health updates. Most were school-aged children. At least 18 people have been hospitalized with complications since the outbreak began, though no deaths have been reported in South Carolina.

“This is an example of what can happen when vaccination coverage decreases below the threshold needed to maintain herd immunity,” the Department of Public Health warned in one advisory, urging residents across the state to check their records and get the measles, mumps and rubella, or MMR, vaccine if they had not done so.

From Spartanburg to Charlotte

For years, North Carolina saw very few measles cases — just 35 between 2005 and 2024, with several recent years reporting none. That changed after the South Carolina outbreak intensified.

By early January, North Carolina had identified five cases, including one in Rutherford County, northwest of Charlotte, that had no clear link to travel or to known South Carolina exposure sites. State officials said that raised concern about undetected spread.

“The lack of an identified source indicates that there are likely other undetected measles cases in the state,” the North Carolina Department of Health and Human Services said at the time.

By March 30, the state’s measles dashboard showed 24 confirmed cases since December and one hospitalization. Nineteen of the infections were in people under 18. About two-thirds of patients were unvaccinated or had unknown vaccination status; nearly a third had received only one MMR dose.

Health officials have flagged areas in and around Asheville and the Charlotte metropolitan region as places where community spread is possible. North Carolina is also testing wastewater at 36 treatment sites for traces of measles virus; four detections have been reported since December.

“Vaccination remains our strongest defense against measles,” state epidemiologist Dr. Zack Moore said in a January statement. “We urge anyone not fully vaccinated to take action now.”

What the CDC is doing on the ground

The CDC’s March 9 announcement described a “comprehensive suite of surge resources and technical assistance” for South Carolina and North Carolina.

In South Carolina, the agency has embedded epidemiologists inside the Department of Public Health and sent additional Epidemic Intelligence Service officers and field staff to the Upstate. Spectrum News reported that three EIS officers would spend at least two weeks in the state in March, focusing on how the virus spread in schools and other community settings and analyzing data from both Carolinas.

Their work includes tracking chains of transmission, supporting contact tracing, advising on quarantine and isolation protocols, and helping classify cases. The CDC is also providing advanced laboratory testing and genomic sequencing to determine whether new infections are linked to the Spartanburg outbreak or represent separate introductions.

Behind the scenes, the agency’s Center for Forecasting and Outbreak Analytics is running models to project how the outbreaks could unfold under different scenarios, such as high or low vaccine uptake and more or less strict adherence to exclusion policies.

At the same time, the CDC has made additional vaccine supplies available upon request and is advising on post-exposure prophylaxis — the use of MMR vaccine or immune globulin for infants, pregnant people and others at high risk after they are exposed.

In its March 9 release, the agency reiterated long-standing guidance that two doses of MMR are highly effective at preventing measles and that serious side effects from the shot are extremely rare.

Dr. Linda Bell, South Carolina’s state epidemiologist, said in an interview with local television that the federal team’s work would “strengthen our ability and others’ ability for containment measures in the future.” She warned that travel around spring break could fuel further spread, noting that cases increased after the winter holidays.

Schools at the center

Schools and child care centers have been at the heart of the response in both states.

South Carolina maintains a School and Childcare Exclusion List that requires children and staff with measles — and those without proof of immunity — to stay home when measles is identified in a facility. During the current outbreak, quarantine orders have affected students at Lyman Elementary, Boiling Springs Middle, D.R. Hill Middle and other schools, sometimes for weeks at a time.

At various points, state officials reported well over 200 people in quarantine and more than a dozen in isolation. Many were school-age children flagged as close contacts of confirmed cases.

The outbreak has also prompted changes to routine vaccination schedules in the hardest-hit areas. Normally, children receive their first MMR dose between 12 and 15 months of age. In the Upstate, health officials are recommending that infants as young as 6 months get an early dose if they live in affected communities or will be traveling there.

Demand for the vaccine has surged. In January, South Carolina providers administered more than 16,800 doses of MMR — a 72% increase compared with the same month a year earlier — including nearly 1,200 early doses for infants ages 6 to 11 months, according to state figures.

To reach families who may not have regular access to pediatric care, the Department of Public Health and local partners have held free MMR clinics in churches and community centers around Spartanburg.

Hospitals have adapted as well. Prisma Health, one of the region’s largest providers, tightened screening and isolation protocols, adjusted visitor policies and reviewed staff vaccination records in response to the outbreak.

North Carolina has issued detailed guidance for schools, child care centers and universities on how to verify immunization, respond to suspected cases and exclude students without documented immunity when required. Counties including Mecklenburg and Guilford have opened extended-hours vaccination clinics and urged families to review their records.

A fragile line of defense

Nationally, the measles resurgence is part of a broader pattern. The United States recorded more than 2,200 cases in 2025, the most since 1991. As of mid-March, the 2026 total had already surpassed 1,300.

Health officials point to several drivers: routine immunization visits delayed during the COVID-19 pandemic, ongoing shortages of pediatric providers in some areas and pockets of vaccine hesitancy fueled by misinformation and political polarization.

Kindergarten coverage with two doses of MMR has fallen below 93% for four consecutive school years, according to federal estimates. The target for community-level protection is 95%. In South Carolina, statewide kindergarten coverage slipped from about 95% to roughly 92% between the 2019–20 and 2023–24 school years. In some Spartanburg-area schools, exemption rates now exceed 9%.

North Carolina’s statewide MMR coverage is similar, but state data show localized gaps in counties around Asheville and Charlotte.

The outbreaks in the Carolinas are unfolding as the Pan American Health Organization has declared that the Region of the Americas no longer meets measles-free criteria because of continued transmission in multiple countries. Experts have warned that the United States could formally lose its own elimination status if large outbreaks continue.

For front-line officials in the Carolinas, the focus remains immediate: identifying cases quickly, isolating them, tracking contacts and closing vaccination gaps.

“This is a vaccine-preventable disease,” Moore said in North Carolina. “We have the tools to stop it.”

Whether those tools are used widely enough — in pediatricians’ offices, school nurse clinics, church halls and mobile vans from Spartanburg to Charlotte — will determine if measles remains a rare emergency or becomes a recurring part of childhood again.