As of March 26, 2026, the Centers for Disease Control and Prevention had confirmed 1,575 measles cases in the United States — a figure that, on current trajectory, will surpass the 2025 full-year total of 2,285 cases before summer ends. Measles was declared eliminated from the United States in 2000. That status — 26 years of continuous recognition — is now at direct risk, and the international body that will make that determination has scheduled its review for November 2026. Canada, the U.S.'s closest neighbor, already lost the same status in November 2025. The chain of events that has brought the country to this point is traceable, documented, and playing out in real time in 31 states, a detention facility in Texas, a university in Florida, and a religious community in South Carolina.
The Numbers: Where Things Stand
The CDC's weekly measles update, published as of March 26, 2026, establishes the baseline: 1,575 confirmed cases, 16 active outbreaks, and cases in 31 states plus New York City. Of those 1,575 cases, 94% — specifically 1,483 cases — are outbreak-associated: 359 linked to outbreaks starting in 2026, and 1,124 from outbreaks that began in 2025 and are still ongoing, according to the CDC data page.
The demographics are stark. Twenty-one percent of cases are in children younger than five years old. Seventy-three percent involve children and young adults aged 19 and under. Ninety-two percent of case-patients are unvaccinated or have unknown vaccination status; only 4% are fully immunized with two MMR vaccine doses, per CDC data.
Seventy-eight cases — 5% of the total — have required hospital care, according to CIDRAP's reporting on the CDC data. The CDC also noted it is aware of probable measles cases being reported by jurisdictions that are not yet lab-confirmed, meaning the actual case count is likely higher than the official 1,575 figure.
No deaths have been attributed to measles in 2026 as of the latest CDC data, according to CIDRAP. In 2025, three people died from measles in the United States — two children and one adult, all unvaccinated, according to The Hill's reporting on the outbreak trajectory.
The 2025 full-year total of 2,285 cases was, according to CIDRAP, the most since 1991. The United States could top that number this spring.
The Biggest Outbreaks
The South Carolina outbreak is the largest individual driver of this year's numbers. More than 997 cases have been reported in South Carolina since October 2025, with 940 of those — 94% — concentrated in Spartanburg County in the state's Upstate region, according to the South Carolina Department of Public Health. The SCDPH confirmed no new cases as of late March and indicated the outbreak could be declared over if no new cases are reported by April 26.
In Texas, 170 cases have been confirmed so far in 2026, including 23 in the most recent weekly update, according to the CDC measles map as reported by CIDRAP. At least 108 of those Texas cases are inside a federal detention facility managed by a private company in Hudspeth County. The Texas Tribune reported on March 26 that four El Paso residents who worked inside the facility are among the patients, potentially exposing the surrounding community.
Arizona has reported 60 cases in 2026 and 280 in a Utah-linked outbreak that started in 2025. Idaho has 23 cases. Florida has 128 cases confirmed by the CDC map — though CIDRAP noted that media reports have counted at least 140, including 104 cases at Ave Maria University in Collier County. Notably, the Florida state health department "does not appear to be tracking measles cases in Florida," according to CIDRAP's reporting.
North Dakota has 26 cases, four of which required hospitalization, according to state health department figures cited by CIDRAP.
The Root Cause: Vaccination Rates in Decline
The measles, mumps, and rubella (MMR) vaccine is highly effective and long-lasting, according to the CDC. For measles specifically, two doses provide approximately 97% protection. The minimum threshold for herd immunity — the point at which enough people are vaccinated to stop community spread — is approximately 95% coverage, according to standard public health guidance.
The United States is no longer meeting that threshold. Vaccination coverage among U.S. kindergartners dropped from 95.2% during the 2019–2020 school year to 92.5% in the 2024–2025 school year, according to CDC data. The CDC calculates that this leaves approximately 286,000 kindergartners at risk during the 2024–2025 school year alone.
The decline is driven by two overlapping trends: a post-COVID disruption to routine pediatric care that suppressed vaccination rates across the board, and an increase in vaccine exemptions. According to U.S. News & World Report's tracking of the outbreaks, the surge in measles is "mostly due to a decline in vaccination rates and an increase in vaccination exemptions."
The scale of the risk from even marginal further decline is quantified by the Common Health Coalition. A 1% decrease in the childhood MMR vaccination rate, according to a Common Health Coalition report cited by U.S. News, could cause 17,000 measles cases, 4,000 hospitalizations, and 36 preventable deaths each year. The U.S. is currently 2.7 percentage points below its 2019–2020 rate — well past the 1% threshold that represents that modeled harm level.
Dr. Dave Chokshi, chair of the Common Health Coalition, was quoted in the coalition's statement: "Vaccination is one of the most powerful investments we can make for the health of our children, but when we fail to maintain high vaccination rates, we all pay the price."
The Elimination Status Question: What It Means and When It's Decided
Measles was declared eliminated in the United States in 2000. "Elimination" in this context has a specific technical meaning: the virus was no longer spreading continuously for more than one year within the country, according to U.S. News. Travelers could import cases, and small outbreaks could occur, but the virus did not establish sustained endemic transmission.
The Pan American Health Organization (PAHO), in a March 2, 2026 update on its website, confirmed that the review of U.S. measles elimination status will take place during the Commission's regular annual meeting in November 2026. PAHO's statement said the review will assess whether endemic transmission has been "re-established" — defined as "uninterrupted circulation of the same virus genotype and lineage for 12 months or more in a specific geographic area."
The PAHO statement noted that "the analysis period for assessing the possible re-establishment of endemic measles transmission" in the United States "corresponds to one year from the onset of the reported outbreaks: 20 January 2025 in the United States." That means by January 2026, the U.S. had already crossed the 12-month threshold of sustained outbreak activity. Whether that meets the technical definition of endemic transmission is what the November review will determine.
The precedent from Canada is instructive. In November 2025, PAHO's Regional Verification Commission concluded that "endemic transmission had been re-established in Canada, where the virus circulated uninterrupted for at least 12 months." Canada had held measles elimination status as part of the Americas regional certification. Its loss triggered the loss of the entire region's status as well, per PAHO's statement.
The U.S.'s situation, with 1,575 confirmed cases across 31 states and multiple outbreaks now in their second year of continuous activity, presents a comparable profile. CNN reported in March that the U.S. elimination status review had been delayed until November from an earlier scheduled date, citing the ongoing analysis by U.S. health authorities including complete viral genome sequencing.
Why It Matters Beyond the Numbers
Measles is one of the most contagious diseases known to medicine. According to the CDC, if one person has measles, up to nine out of 10 nearby people will become infected if they are not protected. That R0 — the base reproduction number — is higher than the coronavirus at its most transmissible variants.
Losing elimination status does not mean measles becomes endemic in the way it was before vaccines — the vaccine is still available, still effective, and still free in the United States. What it means is a formal international acknowledgment that the United States has lost one of its foundational public health achievements, and that the infrastructure of vaccination coverage that made elimination possible has eroded below the threshold required to sustain it.
The practical stakes are real. Children who are too young to be vaccinated — measles vaccination typically begins at 12 months — and immunocompromised individuals who cannot receive live vaccines are protected by community immunity. As that immunity erodes, so does their protection. The 78 hospitalizations already recorded in 2026, and the three deaths in 2025, belong to that category.
The political backdrop adds complexity. HHS Secretary Robert F. Kennedy Jr. has been publicly skeptical of vaccine mandates and standard vaccine safety communications since taking office, and U.S. News tracked that his moves at HHS have "played out against the backdrop of an explosion in vaccine-preventable measles cases." The CDC, DOGE-reduced in staffing, has continued to update its measles data page, but Florida's apparent non-tracking of cases illustrates how state-level public health infrastructure variation can create blind spots in the national picture.
The November PAHO review will make it official. But the data has been available, weekly, in plain sight: the United States is on the verge of losing a public health achievement it took decades to earn and years to quietly let slip away.