South Carolina health officials have reported an “accelerating” measles outbreak in the state in the wake of Thanksgiving travel and a lack of vaccinations, with hundreds of people in quarantine.

The outbreak, which appears centered on a single church and several schools in Spartanburg county in the state’s north-west, according to an epidemiologist for the state’s department of public health, totaled 111 cases.

Of those, 105 were unvaccinated while three were partially vaccinated, state epidemiologist Linda Bell said at a news briefing. A further 254 people have been placed in quarantine as of Tuesday, with 16 held in isolation.

“Accelerating is an accurate term,” Bell said at the briefing. “That is a spike in cases we are concerned about.” She added that South Carolina has “lower than hoped for” vaccination coverage.

In an earlier advisory, the state’s health department reported 27 new cases of measles since Friday. Sixteen of the new cases resulted from exposure at the Way of Truth church in Inman; eight are household members of known cases, and one each attributed to school, healthcare facility or unknown exposure.

“We are faced with ongoing transmission that we anticipate will go on for many more weeks,” Bell said, adding that the uptick in cases “is a significant increase in our cases in a short period of time”.

The state’s measles cases comes as the Centers for Disease Control and Prevention (CDC) reports 1,912 confirmed measles cases across 43 US states this year. Most of those cases are attributed to 47 outbreaks, including a significant outbreak in Texas.

More than half of the cases occurred among children and total of 24 measles cases were reported among international visitors. Two girls died after contracting measles in Texas and a man is suspect of dying from measles in New Mexico.

For comparison, 16 outbreaks were reported during 2024 and 69% of cases (198 of 285) were outbreak-associated, the CDC reported.

The worsening outbreak in South Carolina comes as state health authorities report a decline in the number of students with vaccines from nearly 96% in 2020 to 93.5% in the 2025 school year.

Twenty of the cases in South Carolina involve children under the age of five, while 75 of the cases were detected in children between the ages of five and 17.

Bell said the outbreak of measles was notable in part because the US had declared measles eliminated in 2000, a declaration that means measles had not spread domestically for more than a year.

Bell said “high vaccine coverage was responsible for eliminating ongoing transmission in this country” but that for the past year “we’ve run the risk of losing that designation as a country.”

“What we’d like people to see is that picture: to consider the effectiveness of the vaccine and having this disease essentially go away,” she said.

The rise in outbreaks is partly attributed to mixed messages on vaccines coming from federal health officials, including Robert F Kennedy Jr, the health secretary who has expressed broad skepticism about the number and frequency of vaccines given to children.

However, Kennedy has been in explicit in his support of the MMR vaccine that offers protection against measles, mumps, and rubella.

“The most effective way to prevent the spread of measles is the MMR vaccine,” Kennedy said in a post on X in April after he visited the families of the two West Texas children who died.

Kennedy said he had directed the CDC to “supply pharmacies and Texas run clinics with needed MMR vaccines”, along with other medical supplies.

But in north-west South Carolina, Bell said, the deployment of mobile health clinics offering MMR shots had not been heavily utilized. “I can tell you that a relatively small number of doses was administered at each of the mobile health unit clinics that we offered,” she said.