Measles Cases Confirmed in Nearly Half the US

One of the largest measles outbreaks in over 30 years is happening in South Carolina with 933 associated cases reported by its state health department as of Feb. 10. The outbreak is still centered in the northwest part of the state (including Greenville and Spartanburg) with most of the cases close contacts of known cases. However, the number of public exposure sites indicates that measles is circulating in the South Carolina community, increasing the risk of exposure and the risk of infection for those who are not immune due to vaccination or natural infection. 

Most of South Carolina’s cases (837 cases) are minors under the age of 18 and unvaccinated residents (859 cases).

The large outbreak along the Arizona-Utah border also continues. State health departments report that as of Feb. 10, 272 cases have been confirmed in Utah while 254 cases have been confirmed in Arizona as of Feb. 3.

The California Department of Public Health (CDPH) is urging Californians to check their immunization status and get vaccinated against measles after local health departments have notified the state of multiple recent cases of measles. This includes an outbreak of eight related cases in Shasta County, the state’s first measles outbreak since 2020. All of these individuals were either unvaccinated or had an unknown history of vaccination. Last week, CDPH also issued a Health Alert notifying health care providers to be on the lookout for measles in patients presenting with a fever, rash and other symptoms consistent with measles.

Cases have been reported in Los Angeles, Orange, San Bernardino, Riverside and Shasta counties. Two recent cases visited Disneyland on January 22 and 28 while infectious. Local health officials are working with Disneyland Resort to notify potentially exposed employees, and members of the public that visited Disneyland on either date. As of Feb.9, a total of 17 measles cases have been reported statewide.

As of Feb. 6, the Centers for Disease Control and Prevention (CDC) confirmed 733 measles cases in the U.S. this year. (The CDC is aware of probable measles cases still being reported by jurisdictions and this number is likely to grow higher.) Reported cases have now expanded to 20 states, including: Arizona, California, Florida, Georgia, Idaho, Kentucky, Minnesota, Nebraska, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Utah, Virginia, Washington, and Wisconsin. Six measles cases were reported among international visitors as well.

Eleven outbreaks have now been reported in 2026, and 92% of confirmed cases (671 of 733) are outbreak-associated. Among the outbreak-associated cases, 165 cases are from outbreaks that started in 2025.