2026 US Measles Cases Surpass 2025 Total

The CDC reported 3,471 confirmed measles cases in the United States in 2026 as of September 17. That exceeds the 2,289 cases reported for all of 2025, according to the agency’s measles cases and outbreaks page. The CDC cautions that its 2025 and 2026 case counts are preliminary and subject to change.

Of the 2026 total, 3,454 cases were reported by 47 US jurisdictions, and 17 were reported among international visitors. The national count includes international visitors. The CDC assigns cases to a year according to the epidemiological week of rash onset, which may span the end of one calendar year and the beginning of the next.

The agency reported 39 new outbreaks in 2026. Outbreaks accounted for 3,296 cases, or 95% of this year’s total; 1,920 were linked to outbreaks that began in 2026, and 1,376 to outbreaks that began in 2025. The CDC defines an outbreak as three or more related cases. In 2025, it recorded 48 outbreaks, with 90% of cases linked to outbreaks.

The CDC also reported that measles, mumps, and rubella (MMR) vaccination coverage among US kindergartners fell from 95.2% in the 2019–2020 school year to 92.4% in 2025–2026. The agency estimated that approximately 280,000 kindergartners were at risk during the latter school year. It noted that local vaccination coverage may vary substantially, including pockets of unvaccinated people in states with high overall coverage.

The national figures include only confirmed cases that jurisdictions have notified to the CDC; probable cases are excluded. The agency says states may have more current case and outbreak figures because they report on different schedules. Although the webpage was updated September 23, its 2026 case totals reflect reports as of September 17.

Source: Centers for Disease Control and Prevention. Measles cases and outbreaks. Updated September 23, 2026. Accessed September 24, 2026.