On Jan. 12, 2026, a measles outbreak in South Carolina continues to grow, and now neighboring North Carolina is reporting more measles cases linked to that outbreak. Late last week and into the weekend state officials confirmed 99 new measles cases in the Upstate outbreak, and 200 state residents currently in quarantine. 

“Some cases are travel-related exposures or close contacts of known cases. Other cases have no identified source, suggesting that measles is circulating in the community and could spread further,” the state said in a release. “We have seen measles spread quickly in unvaccinated households here in South Carolina. We also know that it can spread quickly in unvaccinated communities based on outbreaks in other states.”

In total, South Carolina has reported 310 measles cases in the last six months. Of the 310 measles patients, 256 were unvaccinated, two were partially vaccinated, two were fully vaccinated, and 50 had unknown status. The outbreak is the second-largest in the United States right now, behind the Utah-Arizona outbreak, which has seen 390 cases. Of the 310 cases in South Carolina, 206 are in children ages 5 to 17 years, 69 are in kids younger than 5 years, and 29 are in adults. Several exposure sites in recent weeks have been elementary schools. 

Now other states are increasingly reporting measles cases and exposures connected to the South Carolina outbreak. Last week, the Snohomish County health Department in Washington state said three visitors from South Carolina, one adult and two children, visited Washington state while infectious. 

In North Carolina, Mecklenburg County said wastewater levels of the virus were surging, though no cases have yet been identified in the county. North Carolina has reported five measles cases since late December, with four of the five cases connected to exposures in South Carolina’s Upstate region.