US Loses Measles Elimination Status After 25 Years

Measles has returned to the United States after a 25-year absence, following a series of major outbreaks that began in January 2025, the Wall Street Journal reported on Friday (Nov. 13).

For the 2025-2026 period, only 10 states have documented kindergarten vaccination percentages above the required immunity threshold, reflecting a general decline in national measles immunization coverage over recent years. Eight measles-related deaths have been recorded across Pennsylvania, Wisconsin, and New York during the recent resurgence.

Elimination status revoked

The Pan American Health Organization, which serves as the regional office of the World Health Organization for the Americas, reevaluated the country’s measles elimination status and determined it should be revoked, the Wall Street Journal reported.

The U.S. originally achieved elimination in 2000, signifying that the country had gone over a year without continuous domestic spread. Travelers occasionally brought the virus into the country previously, but those instances did not trigger ongoing domestic transmission.

With this decision, the United States joins nations such as the United Kingdom and Canada in seeing a local return of the disease. Nearly 2,300 cases were reported nationwide in 2025, and almost 5,412 confirmed cases have been recorded so far in 2026. Both tallies are likely undercounts.

“When January 2025 picked up, I felt like this might be the point of no return,” Maimuna Majumder, a distinguished scholar in the Computational Health Informatics Program at Boston Children’s Hospital, previously told Live Science. “I do want to just stress that measles elimination has always been a tenuous prospect, and it is, by design, tenuous,” she added.

Falling vaccination rates

Keeping an eliminated disease from resurging requires maintaining vaccination rates above a critical threshold. To ward off major outbreaks, a minimum of 95% of the population must possess immunity acquired through past infection or vaccination, given how rapidly the measles virus transmits.

National measles vaccination rates have fallen in recent years. Just 10 states reported rates above the immunity threshold among kindergarteners for the 2025-2026 school year.

Public health factors

Experts point to several factors driving the downward trend in immunizations. These include declining funds and staff for public health efforts, alongside wavering public trust in vaccines and scientific expertise.

According to experts, the departure of veteran federal health leadership alongside the installation of Kennedy Jr. as health secretary further accelerated this momentum, since modified vaccine guidelines likely create confusion while current federal messaging portrays vaccine safety and efficacy as open questions despite their well-established nature.

Fatalities and complications

Measles infections can cause serious consequences, including long-term disability and death. State health officials said that Pennsylvania documented the country’s initial measles-related fatalities of the year in August, which have since been followed by five additional deaths.

Based on state tallies, one fatality in Wisconsin and another in New York have elevated the overall death count to eight. Approximately 1 to 3 out of every 1,000 U.S. measles cases prove fatal.

Having tallied slightly over 1,500 infections, Pennsylvania’s fatality count exceeds expectations, suggesting that the state’s official figures fail to capture the true volume of cases. Following infection, survivors can suffer lasting medical complications such as neurological damage and immune amnesia, a condition wherein the body’s immune cells lose their historical records of prior infections.

Originally slated for April, the meeting held by the Pan American Health Organization to reassess the standing of the United States was ultimately postponed to November. To restore its status as a measles-free country, the U.S. needs to sustain a 12-month period free of uninterrupted viral transmission.

Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider regarding any medical condition, diagnosis, or treatment plan.

Earlier coverage: USA Loses Measles-Free Status Following Surge in Infections