Measles was eradicated in the US 25 years ago. This week, cases reached a new high.

For the first time since measles was declared eradicated in the United States in 2000, domestic cases have reached a peak, topping 1,288 as of July 9, according to the Centers for Disease Control and Prevention.

Outbreaks have reached 38 states since the beginning of 2025, according to CDC tracking data, resulting in at least 162 hospitalizations. The majority, 92%, occurred in unvaccinated people and children under the age of 19. There have been three confirmed deaths.

Though Demetre Daskalakis, director of the CDC’s National Center for Immunization and Respiratory Diseases, told members of the Advisory Committee on Immunization Practices in a meeting June 25 that cases were hitting a “plateau,” at least 61 new cases have been confirmed since, and one new state has been added to the list.

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Measles is a vaccine-preventable disease that had been considered eradicated in the United States as of 2000, meaning there was no spread and new cases were those contracted only from abroad. But vaccinations have declined, resulting in a growing number of states no longer reporting rates consistent with herd immunity, and infections have returned.

The last outbreak of a similar scale occurred in 2019, when 1,274 cases were confirmed across the country. Just six months into 2025, that number has been surpassed in a grim milestone.

Of all confirmed cases in 2025, 88% are associated with the outbreak, which has centered heavily in the Southwest. Texas has reported 753 cases across 35 counties, and New Mexico reported 95 total cases as of July 9.

In a statement shared with USA TODAY on Thursday, the Department of Health and Human Services said that while it is supporting community efforts to respond to the measles outbreaks, the overall risk of infection remains low.

“Measles risk is higher in U.S. communities with low vaccination coverage, particularly in areas experiencing active outbreaks or closely connected to such areas socially or geographically,” said the statement. “CDC continues to recommend the MMR vaccine as the most effective protection against measles. Vaccination is a personal decision, and individuals should consult their healthcare provider to understand their options and make informed choices about the potential risks and benefits of immunization.”

See how measles cases have stacked up year-over-year since 2000

What is measles and how do you get it?

Measles is a highly contagious, vaccine-preventable disease caused by a virus that primarily, and most severely, afflicts children. According to the World Health Organization, it infects the respiratory tract before spreading throughout the body.

The virus is one of the most contagious infectious diseases; so contagious, in fact, that 90% of unvaccinated people who are exposed end up contracting it. Additionally, 1 in 5 of those people end up hospitalized, according to the CDC.

The MMR vaccine (measles, mumps and rubella) protects against measles with a 97% efficacy rate and is typically given to children as part of the regular vaccine course at ages 12 to 15 months for the first dose and ages 4 to 6 for the second.

RFK Jr. gives mixed messages on measles vaccination

Robert F. Kennedy Jr., the nation’s top health official, has issued mixed messages to parents amid the outbreak, encouraging the vaccine but linking it to adverse outcomes and suggesting remedies experts have warned against, such as the use of vitamin A for prevention and treatment.

Despite Kennedy saying he isn’t anti-vaccine during confirmation hearings, he has continually linked vaccines to autism, cofounded an anti-vaccine group and urged parents not to vaccinate their children. Though the current outbreak has resulted in the first measles deaths in a decade, Kennedy initially called the surge in cases “not unusual.”

Experts have warned against Kennedy’s comments, saying his claims are not based in science and that vaccines are the only effective form of protection.

This article originally appeared on USA TODAY: Measles was eradicated in the US 25 years ago. This week, cases reached a new high.