Measles Update: October 23, 2026

Today, the Centers for Disease Control and Prevention (CDC) reported there were 4588* cases of measles in the US as of October 22, 2026. Week-over-week, the agency added 178 cases, a 4.0% increase. Last week, the federal agency reported there were 4410* confirmed cases.^1,2

The increase is smaller than last week's 8.1% rise, when CDC added 330 cases.² The 2026 total is now roughly double the 2289 cases reported for all of 2025.¹

CDC said there were 4570 measles cases reported by 47 jurisdictions: Alabama, Alaska, Arizona, California, Colorado, Connecticut, Delaware, District of Columbia, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Montana, Nebraska, New Jersey, New Mexico, New York City, New York State, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, and Wyoming. A total of 18 measles cases were reported among international visitors to the United States.¹

The federal agency reports there have been 43 new outbreaks** reported in 2026, and 96% of confirmed cases (4404 of 4588) are outbreak-associated (3020 from outbreaks starting in 2026 and 1384 from outbreaks starting in 2025).¹ One new outbreak was added since last week.²

Hospitalizations and Age Distribution in 2026 Measles Cases

CDC reported 479 hospitalizations among the 4588 cases, or 10%.¹ Last week, the agency reported 451 hospitalizations, which means 28 more patients were hospitalized week-over-week.²

Hospitalization rates varied by age. Children younger than 5 years had a rate of 16% (119 of 766), and adults 20 years and older had a rate of 14% (268 of 1881).¹ Those aged 5 to 19 years had a rate of 5% (91 of 1914).¹

People younger than 20 years account for 58% of cases (2680 of 4588).¹ Adults 20 years and older make up 41% (1881 cases), and the age of 27 cases is unknown.¹

Vaccination Status and Coverage Trends

Ninety-six percent of 2026 patients were unvaccinated or had unknown vaccination status, while 2% had received 1 MMR dose and 2% had received 2 doses.¹ CDC lists 3 measles deaths in 2026, a number the agency says is subject to change as reviews are completed.¹

Kindergarten MMR coverage has fallen from 95.2% in the 2019-2020 school year to 92.4% in 2025-2026, leaving approximately 280,000 kindergartners at risk.¹ CDC is also working with the Council of State and Territorial Epidemiologists to develop a standardized case definition for measles deaths.¹

*It is important to note that the CDC says on its website that the federal agency is aware of probable measles cases being reported by jurisdictions. However, the data on this page only include confirmed cases that jurisdictions notified the CDC about. Therefore, there could be higher numbers in the US overall.

**CDC reports the cumulative number of measles outbreaks (defined as 3 or more related cases) that have occurred this year in the US; states have the most up-to-date information about cases and outbreaks in their jurisdictions.

Continue to check back with Contagion for our weekly updates, news announcements around the disease, and clinician commentary. In addition, we have a measles library of articles and clinician commentary.

References

1. Measles Cases and Outbreaks. CDC. Updated October 23, 2026. Accessed October 23, 2026. https://www.cdc.gov/measles/data-research/index.html

2. Measles Update: October 16, 2026. Contagion. October 16, 2026. Accessed October 23, 2026. https://www.contagionlive.com/view/measles-update-october-16-2026