Measles Elimination Status in the U.S. Under Threat

It’s hard to believe, but the United States officially eliminated measles about 25 years ago. Now, it seems that status is slipping away.

A growing number of scientists are voicing this concern, including a public health expert who recently published an essay making this very point. Jess Steier wrote for the Center for Infectious Disease Research and Policy (CIDRAP), declaring that, “The U.S. has lost its hold on measles elimination.”

Elimination refers to a formal classification indicating that a country has successfully halted the transmission of a disease like measles. The U.S. reached that milestone in 2000, thanks in large part to extensive vaccination campaigns. However, the political climate surrounding vaccines has dramatically shifted in recent years, contributing to a steep decline in vaccination rates. As a result, the country has witnessed numerous measles outbreaks.

The current measles outbreak began in West Texas in January 2025 and has since spread beyond state borders. Last year marked a significant rise in cases, with 2,288 reported— the highest number since the 1990s. Just in the first half of this year, there have already been 2,104 cases.

Public health experts have expressed alarm since late last year, warning that it could lose its elimination status. The decision rests with the Pan American Health Organization, a part of the World Health Organization, which initially planned to evaluate the situation in April. However, U.S. officials requested additional time for data collection, pushing the decision to November.

Dr. Jake Scott, an infectious disease specialist at Stanford, explained that loss of elimination status isn’t just about statistics; it’s a distinct designation. He notes that the virus has been spreading across multiple states for over a year without interruption, suggesting we’ve crossed the threshold for what constitutes elimination.

Indicators of Elimination Status

To determine if a disease has been eliminated, researchers consider several factors. The extensive and continuous nature of outbreaks in the U.S. suggests that the disease is widely circulating. Furthermore, while a significant portion of measles cases used to be imported, now only about 6% are. This substantial shift indicates that most cases are originating within the country.

The strains of the virus also provide critical clues; the strain from the Texas outbreak closely resembles another seen in Utah recently, which is concerning. Steier noted that this indicates a “single family tree” rather than separate outbreaks resulting from international travel.

Potential Consequences

If the U.S. loses its elimination status, immediate consequences may not manifest. Dr. Scott pointed out that no sanctions or restrictions would follow, but it could jeopardize future public health efforts. Losing this hard-earned status represents a breakdown of a system developed over decades—fixing it could be quite costly.

Experts suggest dwindling vaccination rates are a primary factor in the resurgence of measles. When the disease was considered eliminated, incoming cases encountered a significant wall of immunity. Now, numerous gaps in that wall have emerged.

In California, for example, 96% of kindergartners are immunized, just above the necessary threshold to prevent outbreaks. Yet nationally, that number hovers around 92%, with some areas reporting rates as low as 80%, increasing susceptibility to large-scale outbreaks.

Cuts to public health funding have further complicated the management of measles. Dr. Scott emphasized that detecting and controlling measles relies heavily on surveillance and contact tracing, but many resources for these efforts have been reduced. “You’ve got more fuel and fewer firefighters,” he cautioned.

Hopes for the Future

Despite these challenges, public health experts urge that measles control isn’t hopeless. In California, for example, existing protections are holding strong, albeit delicately. Dr. Matt Willis, former public health officer in Marin County, expressed moderate optimism about the state’s situation, emphasizing the importance of sustaining those protections.

Moreover, Dr. Scott believes parents can still be persuaded to vaccinate their children, highlighting that many hesitant parents are not deeply anti-vaccine but rather overwhelmed by misinformation. Addressing vaccine hesitancy requires understanding rather than contempt.

“Every single vaccination is a brick in that wall,” he said, expressing a hopeful attitude that the situation can be reversed.