South Carolina Measles Outbreak Surpasses 840 Cases, Sparks National Concern

Record-Breaking Outbreak in South Carolina

South Carolina is currently experiencing a significant measles outbreak, with the South Carolina Department of Public Health (DPH) reporting 847 cases as of January 30, 2026. This makes it the largest measles outbreak in the United States since the disease was declared eliminated in 2000, surpassing the 2025 Texas outbreak which recorded 762 cases. The outbreak is primarily concentrated around Spartanburg County.

Timeline and Contributing Factors

The DPH officially confirmed the outbreak in the Upstate regions on October 2, 2025. While a majority of the reported cases are close contacts of individuals already infected, the presence of numerous public exposure sites indicates that the highly contagious virus is actively circulating within the community. A significant factor contributing to the rapid spread is the low vaccination coverage in the affected areas, particularly in Spartanburg County, which has fallen below the levels necessary to prevent transmission.

Data from the DPH indicates that 88% of the measles cases in South Carolina have occurred in unvaccinated individuals. Nationally, 93% of measles patients in 2026 were either unvaccinated or had an unknown vaccination status. This trend aligns with a nationwide decline in MMR vaccination coverage among U.S. kindergartners, which dropped from 95.2% in the 2019-2020 school year to 92.5% in the 2024-2025 school year, leaving approximately 286,000 kindergartners vulnerable.

Wider Implications and Public Health Response

The South Carolina outbreak is a primary driver of the more than 500 measles cases reported across the United States in January 2026. Public health experts express concern that the U.S. could lose its measles-free designation due to the resurgence of the vaccine-preventable virus. The outbreak has already led to cases being 'seeded' in other states, including 15 cases in North Carolina and 3 cases in Washington state, linked to individuals who traveled while infectious.

Measles is characterized by initial symptoms such as fever, cough, red eyes, and a runny nose, followed by a distinctive rash. The DPH emphasizes that the Measles, Mumps, and Rubella (MMR) vaccine remains the most effective method of protection. As a result of the outbreak, at least 18 individuals, including both adults and children, have required hospitalization for complications. Furthermore, over 440 unvaccinated individuals, many of whom are schoolchildren, have been placed under quarantine for up to 21 days following exposure.