Measles cases surge to 733 in U.S., officials warn outbreaks

The Centers for Disease Control and Prevention reported 733 confirmed measles cases in the United States as of Feb. 5, 2026, a jump of 145 cases from the prior week that public-health officials say reflects a rapid, early-year surge. The tally was reached within a matter of weeks and is roughly four times the number typically seen in an entire year since measles was declared eliminated in 2000.

Of the 733 cases, 727 were reported by 20 state and territorial jurisdictions: 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. An additional six cases were identified among international visitors to the United States. The CDC said 671 of the 733 cases, or 92 percent, were associated with outbreaks: nine came from outbreaks that began in 2026 and 662 from outbreaks that began in 2025. Two new outbreaks were reported in 2026 as of the Feb. 5 snapshot.

Children and adolescents bore the brunt of the cases. Federal data show 203 cases (28 percent) occurred in children under 5 years, 417 cases (57 percent) in those 5 to 19 years, and 92 cases (13 percent) in adults 20 and older; 21 cases remain with age unreported. Vaccination status remains a central factor: 95 percent of 2026 cases were among people who were unvaccinated or whose vaccination status was unknown, with only 2 percent having received one MMR dose and 4 percent two doses.

Public-health experts and CDC materials cited by news outlets point to declining childhood vaccination coverage as a driver of the resurgence. CDC data cited in recent reporting show kindergarten MMR vaccination coverage slipped from about 95 percent in 2019 to below 93 percent in 2025. Such declines matter because public-health authorities generally hold that herd immunity for measles requires about 95 percent coverage. The CDC also reiterated that “the two‑dose MMR vaccine is about 97% effective at preventing measles infection.”

Demetre Daskalakis, the former head of the CDC branch that tracks diseases including measles, said the pattern was predictable. “Because it’s such an infectious virus, whenever you see measles outbreaks, it in effect highlights areas of the country or communities in which vaccination rates are low,” he said. Daskalakis added bluntly, “I think that this highlights that our defenses are down,” noting that declining vaccination rates have left “about 300,000 kindergarteners unprotected.”

News outlets reporting on the CDC snapshot also relayed state characterizations of the crisis: state officials in South Carolina were reported to describe their situation as “its largest outbreak in recent memory.” Local health departments in several of the listed states have active advisories and vaccination drives.

The 2026 snapshot follows a record 2025 year in which the United States recorded 2,276 confirmed measles cases. Federal summaries referenced hospitalizations but did not include a hospitalization total in the published excerpt; state health departments and the CDC are the sources for more granular figures, including hospitalizations, complications and county-level case counts.

Public-health officials urged parents and communities to check state health department updates and seek MMR vaccination where needed. The CDC posts links to state health departments and real-time updates; state agencies such as the Arizona Department of Health Services, Utah Department of Health and Human Services, and South Carolina Department of Public Health provide local guidance and clinic information.