4,080 confirmed measles cases: what to know about the CDC total

Of the 4,080 cases, 4,062 were reported by 47 jurisdictions, while 18 were reported among international visitors. Jurisdictions update the count with confirmed cases reported by noon on Thursdays, and the CDC says the 2025 and 2026 totals are preliminary and subject to change.

That definition matters: the total tracks cases confirmed and reported to the agency. It is not a count of every infection.

How does the 2026 total compare with 2025?

The 2026 count exceeds 2025’s full-year total by 1,791 cases. By mid-July, the 2026 tally had already passed the 2025 figure, CBS News reported.

Outbreaks account for most confirmed cases in both years. The CDC classifies 3,897 cases in 2026, or 96% of the total, as outbreak-associated. It has reported 42 new outbreaks this year and defines an outbreak as three or more related cases.

For 2025, the CDC classified 2,066 of 2,289 cases—90%—as outbreak-associated. Measles spreads through the air and can spread after an infected person has been in a room. The CDC says outbreaks can grow quickly in communities with lower vaccination rates.

What do vaccination rates add to the picture?

The United States was declared to have eliminated measles in 2000. Since then, kindergarten MMR coverage has declined from 95.2% in the 2019–2020 school year to 92.4% in 2025–2026.

The CDC says vaccination coverage above 95% protects most people through community immunity. The kindergarten figures are national averages; the CDC says coverage can vary considerably from one locality to another.

The agency points to declining kindergarten coverage, gaps within communities and increased global measles activity as factors contributing to more measles activity in the United States. Lower coverage in a community can leave more people vulnerable when the virus spreads.

Which prevention steps does the CDC recommend?

The CDC calls MMR vaccination the best protection against measles. It estimates that two doses are 97% effective at preventing the disease; one dose is 93% effective.

For children, the routine schedule is a first dose at 12 to 15 months and a second at 4 to 6 years. Adult recommendations depend on risk factors and evidence of immunity.

For people exposed to measles who lack evidence of immunity, CDC guidance describes two time-sensitive options. An MMR dose within 72 hours of first exposure may provide some protection. Immune globulin may be given within six days to people at high risk of severe disease.

Anyone who may have been exposed should promptly contact a health care provider or public health department about appropriate next steps.