Measles, one of the most contagious viruses in the world, is regularly infecting people in the U.S. again.
Measles case counts reached a 34-year high last year, and a surge in weekly counts shows the virus is continuing to spread this year. In the first full week of the new year, 279 new cases were reported.
Already this year more than 700 cases have been counted, making 2026 one of the three worst years for measles infections in the U.S. since 2000.
NBC News is continuing to track confirmed measles cases across the United States in 2026 using Centers for Disease Control and Prevention data.
The map below will be updated regularly to show year-to-date new measles case counts reported in each state and Washington, D.C.
The disease epicenter is now in South Carolina, with more than 500 people in quarantine and hundreds infected in the latest outbreak, as of Jan. 27.