Health / Public Health

Measles Cases Pass 5,182, Highest Since 1991

More than double all of 2025, 96% outbreak-linked, 96% unvaccinated or unknown, and an elimination-status review running this week.

Anika WellsAI editorial voice · 1 min read

A vaccine syringe. Kindergarten MMR coverage has fallen to 92.4 percent, below the 95 percent level the CDC ties to community protection. (Whispyhistory, CC BY-SA 4.0)

Summary

US measles cases reached 5,182 through November 5, the most since 1991, as kindergarten MMR coverage fell to 92.4%.

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The United States has confirmed 5,182 measles cases this year, the CDC reported November 6, the highest annual total since 1991 with weeks remaining. [US measles cases reach 5,182, highest since 1991, as elimination status faces review — MK Niralo, reporting CDC figures] [US measles cases top 5,000 as childhood vaccination rates fall — The Trent] [US measles cases climb to 5,182, the highest annual total since 1991 — Broken Arrow Local News, reporting CDC, Reuters and CIDRAP]

The count, current through November 5, is more than double the 2,289 cases recorded in all of 2025. Of this year's cases, 96 percent are linked to outbreaks, and 96 percent involve people unvaccinated or of unknown vaccination status. [US measles cases reach 5,182, highest since 1991, as elimination status faces review — MK Niralo, reporting CDC figures] [US measles cases top 5,000 as childhood vaccination rates fall — The Trent] [US measles cases climb to 5,182, the highest annual total since 1991 — Broken Arrow Local News, reporting CDC, Reuters and CIDRAP]

The CDC counts 43 outbreaks in 2026, with 4,993 of the 5,182 cases tied to one. The latest week alone added 330 cases, the 13th straight week of triple-digit growth, per the University of Minnesota's CIDRAP. The largest state outbreak is Pennsylvania's: 1,487 cases across 45 counties and 287 hospital admissions, per the state health department. The CDC lists four measles-associated deaths nationally. Both that figure and the case total are preliminary and can be revised; state-level reporting associates more deaths than the CDC has so far confirmed, a gap that is, at this stage, a confirmation lag rather than a settled count. [US measles cases reach 5,182, highest since 1991, as elimination status faces review — MK Niralo, reporting CDC figures] [US measles cases top 5,000 as childhood vaccination rates fall — The Trent] [US measles cases climb to 5,182, the highest annual total since 1991 — Broken Arrow Local News, reporting CDC, Reuters and CIDRAP]

The coverage slide explains the opening. Kindergarten MMR coverage fell to 92.4 percent in the 2025-26 school year, from 95.2 percent in 2019-20, leaving about 280,000 kindergartners without documentation of a completed series, while exemptions rose to 4.2 percent. The CDC's own benchmarks say communities are protected above 95 percent coverage, and that two MMR doses are 97 percent effective against the disease. What happens next is procedural: a Pan American Health Organization commission meets November 10 to 13 to review whether the United States still meets the criteria for measles elimination, a status held since 2000. The review is a technical assessment, with findings expected next week. [US measles cases reach 5,182, highest since 1991, as elimination status faces review — MK Niralo, reporting CDC figures] [US measles cases top 5,000 as childhood vaccination rates fall — The Trent] [US measles cases climb to 5,182, the highest annual total since 1991 — Broken Arrow Local News, reporting CDC, Reuters and CIDRAP]

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