The United States has recorded 4,588 confirmed measles cases in 2026, according to the update the Centers for Disease Control and Prevention published on October 23 with data through October 22. The figure includes 18 cases among international visitors, and 47 jurisdictions have reported at least one.
The weekly increase was 178 cases, or 4.0% — the slowest in several weeks. The previous update had added 330 cases, an 8.1% jump. One week of deceleration is not a trend, but it is the first since the late-summer acceleration.
Who is getting sick
The vaccination breakdown is the single most consistent number in the CDC's measles reporting this year, and it has barely moved: 96% of the confirmed cases were in people who were unvaccinated or whose vaccination status is unknown. Two percent had received one dose of the MMR vaccine and two percent had received both.
By age, people under 20 account for 58% of the cases — 2,680 — and adults 20 and older for 41%, or 1,881. The age of 27 patients is unknown.
Hospitalization does not follow the case curve evenly. Overall, 479 patients have been admitted, 10% of the total, up from 451 a week earlier. But the rate is 16% among children under 5 and 14% among adults 20 and older, against 5% for the 5-to-19 group — the two ends of the age range are where the disease sends people to hospital.
Three deaths have been recorded in 2026. The CDC marks that figure as provisional, "subject to change as reviews are completed."
Outbreaks, not scattered cases
This is not a year of isolated infections. The agency counts 43 new outbreaks opened in 2026, one more than the previous week, and 4,404 of the 4,588 cases — 96% — are tied to an outbreak rather than standing alone. Of those, 3,020 belong to clusters that started this year and 1,384 to clusters carried over from 2025.
That concentration is what keeps the United States' elimination status in question. Measles was declared eliminated in the country in 2000, a status that depends on the absence of continuous domestic transmission for twelve months rather than on the absence of cases. Chains of transmission that run across a calendar year are precisely what the definition is built to detect.
Reporting from the Centers for Disease Control and Prevention and ContagionLive.
