US risks losing its measles-free status as cases hit 4,410 in 2026

For Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota, measles had rarely been a regular subject on his Osterholm Update podcast before 2025. By September 2026, it had become an urgent discussion. Osterholm has more than 50 years of experience in infectious-disease epidemiology.

The change began in West Texas, where two measles cases brought from abroad arrived on 20 January 2025. The outbreak that followed spread rapidly through under-vaccinated communities.

The United States had been declared to have eliminated measles in 2000. It now faces a review of that designation in November 2026, when the Measles and Rubella Elimination Regional Monitoring and Re-Verification Commission holds its sixth annual meeting.

There were 2,289 confirmed measles cases in the United States in 2025, compared with 285 in 2024. By 15 October 2026, the country had recorded 4,410 confirmed cases for the year, its highest annual total since elimination was declared.

The central issue is no longer chiefly the arrival of cases from abroad. In 2026, 6% of cases were imported, compared with 40% during the elimination years, a pattern pointing to domestic transmission as the force behind the current outbreak.

As of 16 October 2026, 2,844 confirmed cases were linked to outbreaks that began in 2026 and 1,384 to outbreaks that began in 2025. A total of 96% of confirmed cases, or 4,228 of 4,410, were associated with outbreaks, and 42 new outbreaks had been reported in 2026. There were also 18 reported measles cases among international visitors to the United States.

The figures are far beyond the benchmark for maintaining elimination status, which is fewer than one case per 10 million people each year. Early in 2026, the US was recording more than 90 cases per 10 million people.

Vaccination coverage has also fallen. Kindergarten coverage declined from 95.2% to 92.4%, below the roughly 95% level of immunity needed for measles to die out on its own.

The US has confronted a warning before. In 2019, it recorded 1,274 measles cases. From 2020 through 2024, there were 527 confirmed cases in total. The scale of the outbreak that began in 2025 has eclipsed that earlier resurgence, with transmission now largely occurring within the country.

Measles vaccination has long been central to the country’s control of the disease. The first vaccine was licensed in 1963. From 1989 to 1991, more than 55,000 Americans became ill and more than 100 died from measles. The elimination designation achieved in 2000 followed decades of vaccination campaigns.

Canada lost its own measles-elimination status in November 2025 after a year of continuous local spread. The Pan American Health Organization’s November review will measure the US record from the Texas outbreak that began in January 2025.

What the commission will decide, and the formal consequences of any loss of status, remain unknown.