Measles is having its worst year in the United States since the disease was declared eliminated here in 2000. Missouri, so far, has stayed out of it. The state has confirmed four cases in 2026, according to federal and state case counts. It counted six in all of 2025 and two in 2024.
Four cases in seven months is a small number by any measure; it is also twice what Missouri recorded in all of 2024, with five months left on the calendar. No Missouri outbreak has been declared, and the state’s cases have not been linked into a chain of local spread.
The national picture is a different one. Confirmed cases reached 2,318 as of July 23, passing the 2,289 counted in all of 2025, according to a federal report released Friday. Cases have now turned up in 44 states and the District of Columbia.
What the national numbers show
In both 2025 and 2026, 93% of confirmed cases were in people who were not vaccinated, most of them younger than 20. Hospitalizations are down from last year, 151 so far against 243 for all of 2025, and no deaths have been reported this year; three people died in 2025. The single worst week came in mid-January, when nearly 300 new cases were reported.
The heaviest current case loads are in South Carolina with 670, Utah with 522, Texas with 188, Virginia with 176 and Pennsylvania with 134. Every one of those states except Virginia reports childhood vaccination coverage below the 95% threshold public health officials consider necessary to stop measles from spreading. Virginia’s statewide rate is 95.6%, but its outbreak is centered in two rural counties west of Richmond where local measles vaccination coverage runs under 75%.
The last time the country counted more cases than this was in the 1990s, when national vaccination programs were still ramping up. There were 9,643 cases in 1991 and nearly 28,000 in 1990.
Why the Missouri count may not hold
Most states, Missouri included, now report childhood vaccination rates below 95%. That threshold matters because it protects the people who cannot be protected any other way: infants too young for the shot, people who cannot be vaccinated for medical reasons, and anyone whose immunity has faded.
Only 90% of Missouri kindergartners had completed the measles, mumps and rubella series in the 2024-25 school year, according to the Missouri Department of Health and Senior Services, down from 94.6% five years earlier. Some Missouri counties are near 75%. About 5% of Missouri kindergartners had a non-medical exemption on file, against a national rate of roughly 3.4%.
That gap between a low case count and real protection is the thing state health officials keep pointing at. Dr. William Moss, who directs the International Vaccine Access Center at Johns Hopkins University, said in a published statement that high coverage has kept measles at bay for decades by protecting even the unvaccinated. Where there are “pockets of susceptible individuals” across a broad age range, he said, the virus takes hold and moves fast.
Delaware showed how quickly that can happen. The state declared an outbreak this week after its first measles cases in a decade climbed to five in a matter of days. Delaware’s child vaccination rate is 94.1%.
Oklahoma has gone the other direction. Its childhood vaccination rate is 88.7% and it saw 20 cases last year, but only one so far in 2026, after a foundation sent a mobile health van around the state to vaccinate thousands of children.
What is at stake
The Pan American Health Organization is scheduled to review the United States’ measles status in November and to consider revoking the country’s “elimination” designation, as it did for Canada last year.
Measles spreads through the air and can linger in a room after an infected person leaves. Two doses of the MMR vaccine are 97% effective at preventing it; one dose is 93% effective. Before the vaccine, the CDC estimates, measles put about 48,000 Americans in the hospital and killed 400 to 500 every year.
Parents who are unsure whether a child is current on the two-dose series can check with their family doctor or their county health department, which can also pull records from the state immunization registry.
Reporting from Tim Henderson of the Missouri Independent, part of States Newsroom, contributed to this story. Case counts and vaccination coverage figures are from the U.S. Centers for Disease Control and Prevention and the Missouri Department of Health and Senior Services. The 2025 and 2026 national counts are preliminary and subject to revision.