America recently passed a serious measles milestone
As the US officially crosses the 1,000 measles case mark in 2026, experts say infection rates are rising much faster this year than in previous years.
A sign pointing the way to measles testing in Seminole, Texas on February 27, 2025.
Jan Sonnenmayer/Getty Images
The US has officially surpassed 1,000 measles cases in 2026. Centers for Disease Control and Prevention latest disease tally It is learned that, as of February 26, measles infection has been confirmed in 1,136 people. This means that, in just two months, the national total is close to half of all 2,281 confirmed cases reported in 2025.
Measles is a vaccine-preventable viral disease that is highly contagious and potentially fatal. The US was declared measles-free in 2000, but experts say the achievement is certain to be reversed. Infection rates this year are rising at a much faster rate than during the outbreak that began in West Texas in 2025. The spike has alarmed public health experts, many of whom blame declining vaccination rates against measles for the disease’s resurgence.
“Reaching 1,000 (cases) in February is unprecedented, but it’s not because there’s anything new about the virus or the disease like there are new strains of flu. It’s unprecedented because it’s preventable,” says Amy Winter, a demographer and epidemiologist at the University of Georgia’s College of Public Health. “This is a reflection of the recent decline in 100 percent vaccination rates.”
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The CDC’s numbers are likely an underestimate, and there are likely many more cases in the US that are undetected or unreported. The majority of confirmed cases — 90 percent — are linked to surges in more than a dozen states, with a persistent outbreak in South Carolina driving the majority of infections this year. South Carolina Department of Public Health on February 27 A total of 985 cases were registered From autumn 2025 onwards; Of these, 919 cases were in people who had not received the measles, mumps and rubella (MMR) vaccine.
Last year, 11 percent of people infected with measles were admitted to hospital. The disease can cause an itchy rash, fever, severe brain swelling and death. Two children and one adult died from the infection last year – all three people were not vaccinated.
“When you get vaccinated, it’s not only helping your own family or children, but it’s also helping your community,” says Walter Orenstein, an epidemiologist and professor emeritus at Emory University School of Medicine.
The MMR vaccine is highly protective against measles — the shot protects people up to 97 percent for life after receiving its two recommended doses. But because measles is so contagious, communities need a high level of herd immunity — meaning at least 95 percent of the population needs to be immune from vaccination or prior infection — to stop the disease from spreading. Orenstein points out, in particular, children under 12 months of age and people who are immunocompromised or have medical conditions that prevent them from getting the high herd immunity the vaccine benefits.
“Failure to vaccinate not only puts those children or individuals at risk, but also puts the community at risk, including people who have legitimate medical conditions and who cannot be vaccinated,” he says. “With declining immunity, we have a real risk of measles becoming endemic again (in the US) and infecting more people and potentially killing more people.”
Since eradication was achieved in 2000, several cases of measles occur each year in the United States, usually as a result of people becoming infected through exposure abroad. But from 2025 onwards, that relatively controlled caseload is no longer there. Winter says what’s happening now is evidence of more local transmission within the country. If the chain of local transmission continues for more than 12 months, the US will lose its measles-free status. The Pan American Health Organization is set to review the Americas’ measles elimination status in April.
“In my mind, we have already lost the status of elimination,” says Winter.
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