Some children affected by measles in the ongoing South Carolina outbreak have developed a serious complication of the disease called encephalitis, or swelling of the brain, state epidemiologist Linda Bell said on Wednesday. The South Carolina measles outbreak began in October with a handful of infections. It’s not known how many children in South Carolina have developed this serious complication. Under state law, measles cases must be reported to the South Carolina Department of Public Health, but measles hospitalizations and complications do not need to be disclosed. Over 7,000 more doses of the MMR vaccine were given statewide in South Carolina this January compared to January 2025, a 72 percent increase.