CDC reports 1,362 confirmed measles cases across 31 states in 2026

The United States has recorded 1,362 confirmed measles cases as of March 12, 2026, according to the CDC. Cases have been reported across 31 jurisdictions, with 94 percent of them linked to ongoing outbreaks rather than isolated individual exposures. Fourteen new outbreaks have been declared in 2026 alone. The states reporting the highest case counts include California, Texas, New York, and Florida, all of which have large populations and, in several cases, communities with lower vaccination coverage than the national average.

The scale of the 2026 outbreak is already raising questions about whether the United States will lose its measles elimination status. The CDC declared measles eliminated in the US in the year 2000, meaning the country no longer had continuous, endemic transmission. Maintaining that status requires keeping case counts low and preventing sustained chains of transmission. An outbreak running across 31 states simultaneously, with hundreds of cases per month in early 2026, does not fit the pattern of a country confidently holding onto elimination.

What is driving the 2026 measles surge

Declining MMR vaccination rates are the primary driver. The CDC's National Immunization Survey found that MMR vaccination coverage among children aged 19 to 35 months dropped to 92.7 percent in 2023, down from 95.2 percent in 2019. Measles requires approximately 95 percent population immunity to prevent sustained transmission, which means the national average is now below the threshold required for herd protection. In specific counties and communities with concentrated vaccine hesitancy, coverage can fall far below the national figure, creating conditions where a single imported case can seed a large outbreak.

The Surgeon General's office noted in its February 2026 advisory that non-medical vaccine exemptions for school-age children have increased in 41 states since 2019. In several states, personal belief exemptions require no medical justification. Children who are not vaccinated are concentrated in the same schools and communities, which means a measles case introduced into one of those clusters can spread to dozens of unvaccinated contacts before public health officials are aware of the index case.

The threat to US measles elimination status

The Pan American Health Organization, which oversees regional disease elimination certifications in the Americas, uses specific criteria to assess whether a country has sustained elimination. Outbreaks that last longer than 12 months or that demonstrate continuous endemic chains of transmission trigger a re-evaluation of elimination status. The United States came close to losing its status in 2019, when the CDC recorded 1,282 cases in a single year, the highest count since 1992. The 2026 total has already surpassed 2019's full-year number with roughly nine months remaining in the calendar year.

Losing elimination status would have real consequences beyond the immediate public health impact. It would affect US travelers' standing in countries that screen for measles risk at the border, complicate the CDC's diplomatic relationships with global health partners that have relied on the US as a model for elimination programs, and create a new burden for state and local health departments that would need to implement re-elimination protocols. The World Health Organization documented 107,500 measles deaths globally in 2023, almost entirely in countries without sustained high vaccination coverage.

How measles spreads and why the numbers grow fast

Measles is among the most contagious infectious diseases known. Its basic reproduction number, the average number of people one infected person will infect in a fully susceptible population, is estimated between 12 and 18. By comparison, seasonal influenza has a reproduction number of roughly 1.2 to 1.4. That difference means measles spreads through a community of unvaccinated people at a speed that most people find difficult to intuit. A single unvaccinated person with measles who visits a school, a place of worship, or an airport can expose dozens of unvaccinated contacts before symptoms appear, since measles is contagious for up to four days before the characteristic rash develops.

Children under five and adults over 20 face the highest risk of serious complications. These include pneumonia, which occurs in about 1 in 20 measles cases, and encephalitis, which occurs in roughly 1 in 1,000 cases and can cause permanent brain damage. A rare but invariably fatal complication called subacute sclerosing panencephalitis can develop years after measles infection, most commonly in children who contracted measles before age two. The CDC's 2026 case data includes hospitalizations in approximately 10 percent of reported cases.

What public health officials are doing and what is not working

State and local health departments have deployed outbreak response teams to the highest-burden jurisdictions, conducting emergency vaccination clinics and contact tracing for confirmed cases. The CDC has authorized the use of immune globulin, a concentrated antibody preparation, for unvaccinated individuals with high-risk exposures who cannot receive the MMR vaccine immediately. Immune globulin can prevent or reduce measles severity if given within six days of exposure.

The structural problem is that outbreak response is reactive by nature. Vaccination clinics and contact tracing address cases that have already happened. They do not address the underlying decline in routine vaccination coverage that created the conditions for sustained outbreaks. Several states have introduced legislation in early 2026 to tighten non-medical exemption requirements, including proposals in California, Washington, and Michigan that would require physician documentation for all exemptions. California's 2015 SB 277, which eliminated personal belief exemptions after a Disneyland measles outbreak sickened 125 people, produced a measurable increase in MMR vaccination coverage in the years following its passage, with kindergarten coverage rising from 92.9 percent in 2014 to 95.1 percent by 2018 according to the California Department of Public Health.