2025 proved to be a terrible year for measles, with the US reaching a toll not seen in decades.

According to the latest data from the Center for Disease Control and Prevention, there have been more than 2,000 recorded cases of measles this year. Most of these infections occurred in unvaccinated children. Several outbreaks are still ongoing, and the US is likely to lose official measles-free status as early as next month.

A record-breaking year

As of December 23, there were 2,012 confirmed cases of measles in the US, the CDC said reported last week.

The number is the highest seen since measles was locally eradicated in the US in 2000, surpassing the previous modern high of 1,274 cases in 2019; it was also the most since 1992, which saw more than 2,000 cases. However, experts say these current numbers are almost certainly low.

The largest outbreak began in early January in parts of Western Texas. But measles has spread far and wide in the US this year, with cases seen in 43 states, along with 50 different outbreaks. About two-thirds of reported cases occurred in children under the age of 18, and 93% involved people who had not been vaccinated or had unknown vaccination status. Three people in the US have died from measles this year, while 227 have been hospitalized.

The official return of measles

Although the outbreak in Texas formally ended in August, there is concern that some of the current outbreaks are genetically linked to it. If that is true, we will soon pass the one year mark of measles circulating locally in the country. And when that happens, the World Health Organization is expected to declare measles officially back in the US

The US is hardly alone in welcoming measles back. In November, Canada equally lost its measles eradication status. Viral disease has also resurrected in many parts of Europe.

The return of measles has been fueled by declining vaccination rates. It was a problem that preceded the installation of Robert F. Kennedy Jr.,—a longtime foe of vaccines—as head of the US Department of Health and Human Services. But Kennedy didn’t HELPED the situation, even.

Last year, for example, RFK Jr. and its allies the people’s access to certain vaccines. He also reduced the workforce at the CDC and other health agencies, as well as personally firing senior officials who refused to support his anti-vaccine policies. And during the measles outbreak in Texas, he recommended unsupported treatments like cod liver oil that might have more at risk some children. Next year, he may succeed even more dramatic shortening the childhood vaccination schedule.

A positive silver lining is that the overall vaccination rate for measles (over 90%) is still high in the US, at least for now. But it has decreased recently and it is not high enough to ensure herd immunity for people who cannot be vaccinated, such as small children (the first measles, of three, is usually not given until one year). So while most Americans will remain protected against measles, it may continue to cause widespread outbreaks in vulnerable regions for the foreseeable future.

2025 is a bad year for measles, but the worst may be yet to come.