“Accelerating is an apt term.” Those words from Dr. Linda Bell, state epidemiologist of South Carolina, underlined the gravity of a measles outbreak gripping the northwest part of that state, where 111 cases have been confirmed and transmission shows no signs of slowing. Just five days after Thanksgiving gatherings, 27 new infections cropped up, with Bell pointing to holiday travel and persistently low vaccination rates against measles-mumps-rubella as cause.
In Spartanburg County, the K-12 MMR vaccination rate is 90% for the 2024–25 school year, well below the 95% threshold experts say is needed to stop outbreaks. Greenville County fares only marginally better, at 90.5%. These gaps open communities up to a virus that is the most contagious known to science, capable of lingering in the air for hours and infecting nearly every unvaccinated person exposed.
The epicenter of the outbreak encompasses a number of schools and a church in Spartanburg County, where 254 people are now in quarantine for 21 days. For some unvaccinated students, this is their second quarantine since the year began-a total of 42 days away from the classroom. While necessary, these sorts of measures keep young people out of the classroom and put extra burdens on families.
What’s happening in South Carolina is part of a larger national and regional experience. Nationally, the Centers for Disease Control and Prevention is reporting 1,912 measles cases across 43 states in 2025-a number not seen in decades. Other surges are happening in Western states: Arizona has recorded 176 cases; Utah has recorded 115, including one linked to a child care facility where kids were exposed daily for a week. In Colorado’s Montezuma County, an unvaccinated child came down with measles without known travel or contact, suggesting undetected cases in the area.
Most of the infections in the country have been among unvaccinated children and teenagers. This reflects a concerning drop in vaccination coverage since the COVID-19 pandemic, during which routine childhood immunizations dropped substantially. Modeling studies put even modest declines at the level of leaving 1 in 8 U.S. children susceptible to measles, with pockets of under-vaccinated communities serving as active transmission reservoirs.
Other efforts to improve immunity in South Carolina have included mobile health clinics offering vaccinations for MMR, but turnout has been low. “A relatively small number of doses was administered at each of the mobile health unit clinics that we offered.” Bell said. This runs somewhat counter to the evidence from COVID-19 response efforts, in which mobile clinics were particularly effective at reaching underserved populations. Thus, studies revealed that in emergency settings, Black, Hispanic, and uninsured individuals were significantly more likely to use mobile clinics, particularly when supplies were in short supply.
Parents and caregivers are reminded that two doses of MMR vaccine, one dose administered around a child’s first birthday and another around the fifth birthday, provides 97% protection against measles. Moreover, post-exposure prophylaxis given within 72 hours after exposure will prevent illness among the unvaccinated who have recently been exposed. Public health experts emphasize getting updated on missed shots, most especially for those children who missed shots during pandemic-related disruptions. Outbreak-related anxiety management is important.
Experts recommend the best way to cope with anxiety stemming from outbreaks is with things one has control over: checking vaccination records, making catch-up doses appointments, and tracking credible health news. By limiting exposures to misinformation-which may have previously perpetuated vaccine hesitancy-families can make informed decisions. The CDC estimates that herd immunity cannot be lower than 95% for protection; otherwise, outbreaks race through schools and places of worship and community events.
With vaccination rates still low and many traveling over the holidays and with the spread in schools and churches, it is a perfect storm, warns Bell: transmission “will go on for many more weeks.” For families, timely vaccination remains the best shield-not just protecting individual children, but helping to restore the collective immunity needed to stop measles in its tracks.
