US measles cases surpass 2025 total, hit highest level since 1991

Confirmed measles cases in the United States have climbed to 2,318 in 2026, surpassing the total for all of 2025 and marking the country's highest annual case count since 1991, according to the latest data from the Centers for Disease Control and Prevention (CDC).^1,2

The numbers as of July 23

As of July 23, 2026, the CDC had confirmed 2,318 measles cases nationwide, reported by 45 states and jurisdictions plus the District of Columbia. Sixteen of those cases involved international visitors. There have been 35 new outbreaks reported in 2026, and 93% of confirmed cases (2,153 of 2,318) are outbreak-associated — 782 tied to outbreaks that began this year and 1,371 tied to outbreaks that started in 2025 and have carried into 2026.¹

The CDC updates its case count weekly, drawing on confirmed reports submitted by state, local, tribal, and territorial health departments as of noon each Thursday. The agency has noted that some jurisdictions are also reporting “probable” cases that haven’t yet been confirmed, which means real-time state tallies can sometimes look higher than the national figures CDC publishes.¹

Surpassing a record-setting 2025

The 2026 total has now overtaken the full-year 2025 count of 2,289 confirmed cases, which itself was the highest annual tally in decades. Last year's cases were spread across 48 outbreaks; this year has so far produced 35. Before this two-year run, 2024 saw just 16 outbreaks account for 285 cases, and 2023 saw only 59 cases nationwide. The last time the U.S. recorded more cases than in 2025 or 2026 was 1991, when the CDC confirmed 9,643 cases, and the last time annual totals came close was 1992, with 2,126 cases.¹

Measles was declared eliminated in the United States in 2000, meaning the virus no longer circulated continuously within the country. Some public health specialists say the country is now at risk of losing that elimination status, citing declining vaccination rates, waning fear of the disease, eroded trust in public health institutions, and inconsistent federal messaging.

Where outbreaks are active

New outbreaks have recently emerged in Arizona, Delaware, and Wyoming. Pennsylvania's health department has reported 132 cases, with 27 diagnosed in the past week alone. An outbreak centered on Piedmont Health District in central Virginia that began in May has logged 177 cases but appeared to be slowing as of early July, with no new cases reported since July 4.² Earlier in the year, an outbreak centered on Spartanburg, South Carolina, grew to more than 600 cases before ending with nearly 1,000 total cases recorded, according to the Johns Hopkins University measles tracker.²

Who is getting sick

The majority of 2026 cases have been confirmed among children and teenagers aged 19 and younger, and about 1 in 10 children under age 5 who have contracted measles this year have been hospitalized. Ninety-three percent of cases are among people who are unvaccinated or whose vaccination status is unknown, while 3% involve people who received 1 dose of the MMR vaccine and 4% involve people who received the recommended 2 doses.¹

Two doses of MMR vaccine remain about 97% effective at preventing measles, and a single dose is roughly 93% effective. Breakthrough infections in fully vaccinated people do occur, particularly in communities experiencing active outbreaks where the virus is circulating heavily, but the CDC says the share of such cases has stayed consistent with prior years.¹

Why vaccination coverage matters

MMR vaccination coverage among U.S. kindergartners was 92.5% during the 2024–2025 school year, down from 95.2% in 2019–2020 and below the 95% threshold generally considered necessary to sustain community immunity against measles. Local coverage rates vary considerably, and pockets of unvaccinated people can exist even in states with strong overall vaccination numbers.¹

Untreated, measles can be severe. Before the vaccine became available, the disease hospitalized an estimated 48,000 people and killed 400 to 500 people in the U.S. every year. Health officials continue to urge anyone who is unvaccinated, particularly those planning international travel, to talk to a healthcare provider about getting the MMR vaccine.¹

References

1. Centers for Disease Control and Prevention. Measles cases and outbreaks. Updated July 24, 2026. Accessed July 24, 2026. https://www.cdc.gov/measles/data-research/index.html

2. U.S. Measles Tracker Tracking Measles Cases in the U.S. Johns Hopkins University Bloomberg School of Public Health. Updated July 24, 2026. Accessed July 24, 2026. https://publichealth.jhu.edu/ivac/resources/us-measles-tracker