A record-breaking measles outbreak concentrated in Texas and New Mexico reveals the consequences of falling MMR vaccination rates and signals the urgent need to rebuild trust in public health before eradicated diseases return for good.
Editorial: Measles outbreaks in the United States in 2025: Practice, policy, and the canary in the coalmine. Image Credit: nobeastsofierce / Shutterstock
In a recent perspective piece published in the journal New Microbes and New Infections, researchers described the current state of measles outbreaks, with a focus on the United States, and highlighted risk factors for the disease, as well as recommendations for public health policy and clinical practice.
Without immediate action by policymakers and medical professionals, many communities could be at risk of severe disease outbreaks, leading to the return of endemic measles transmission across the U.S.
Global measles outbreaks
The Centers for Disease Control had reported 884 cases of measles across the U.S. by April 2025, with 11 outbreaks spanning 29 states. Texas was the hardest hit, reporting 646 cases, while New Mexico reported 65.
Most infections are clustered along the border shared by Western Texas and Southern New Mexico, accounting for over 90% of Texas cases and nearly all New Mexico cases. Gaines County in Texas has 393 cases, accounting for more than any individual state, and saw two child deaths, both unvaccinated, with one child from the local Mennonite community. Both children died in Lubbock. A third fatality, an unvaccinated adult, occurred in Lea County.
These figures marked the highest measles numbers the U.S. had seen since the disease was declared eliminated in 2000. Previous spikes were far lower, with 667 cases in 2014 during the “Disneyland Outbreak” in California or 1,274 in 2019 among New York Orthodox Jewish communities. Alarmingly, 2025 numbers nearly surpassed the 2019 total within just a few months.
As of the latest CDC update, the U.S. has now reported 1,197 measles cases, just 77 cases short of the 2019 total, which had been the highest since the national elimination of measles was declared in 2000. Measles activity has now been confirmed in 35 states, up from 34 the previous week, likely reflecting Arizona’s first reported cases of the year. Four new outbreaks were reported, bringing the total to 21 nationwide, compared to just 16 outbreaks in all of 2024. Notably, 90% of this year’s measles cases have occurred as part of outbreaks, a rise from 69% last year, indicating the expansion of clusters of sustained transmission.
Internationally, measles cases have also been surging.
Europe is experiencing record levels, particularly in Kazakhstan and Romania. The European Centre for Disease Prevention and Control (ECDC) has reported that, in the 12 months from April 2023 to March 2024, there were 56,634 measles cases across 41 countries. Five countries, Kazakhstan, Romania, Kyrgyzstan, Azerbaijan, and the Russian Federation, accounted for 85% of all cases. Alarmingly, 11 countries reported more than 100 cases per million population, far exceeding the World Health Organization's (WHO) threshold for measles elimination. Hospitalization was required in 71% of reported cases, and five measles-related deaths were documented. This escalation highlights immunity gaps and declining vaccination coverage in parts of the region, posing challenges to achieving elimination goals.
Africa remains heavily affected, with no country achieving elimination. These patterns highlight the growing global hesitancy towards vaccines.
Disease risk factors
The current surge in American measles cases is not driven by immigration but by declining vaccination coverage and domestic transmission. Most cases originate from American residents who traveled abroad and returned infected.
Because measles is extremely contagious, around 95% of the population should have immunity to prevent outbreaks, but national vaccination rates fall short. In 2023, less than 93% of children had two doses of the measles, mumps, and rubella (MMR) vaccine, and coverage is even lower in certain communities.
These estimates also exclude some undocumented and homeschooled children, who are less likely to receive vaccines, leaving numerous unprotected clusters. This year, 97% of measles cases occurred in individuals who were not vaccinated.
One example is Gaines County in Texas, which has the state’s lowest vaccination rates and the highest number of cases. A major factor is the Mennonite community in the Old Colony, which maintains conservative traditions, resists assimilation, and has low access to healthcare and public health messaging, partly due to language barriers. This group is distinct from the Mennonite Church of America and typically speaks a Low German dialect. Although their doctrine does not explicitly prohibit vaccinations, cultural conservatism and historical exclusion from public health initiatives contribute to under-vaccination.
Their low vaccination rates mirror other under-vaccinated groups like New York Orthodox Jews, the Ohio Amish, and clusters in California, each of which has faced recent outbreaks.
The coronavirus disease 2019 (COVID-19) pandemic disrupted routine vaccinations and amplified public skepticism about all vaccines. Even after pandemic restrictions were lifted, MMR vaccine uptake has continued to decline, fueled by political polarization and growing far-right ideologies that promote distrust of science and public health.
This trend aligns with global patterns; worldwide MMR vaccination rates fell to a 20-year low in 2021 and remain below target levels.
Additionally, rising anti-immigration sentiment affects healthcare access for undocumented immigrants, who face barriers like cost, fears of deportation, and language obstacles.
Texas, with the second-largest undocumented population, risks expanding vulnerable groups. Ensuring equitable vaccination is vital for protecting public health and maintaining herd immunity.
Implications for policy and medicine
Measles poses significant risks mainly due to its serious complications, including pneumonia and brain inflammation, which can be fatal.
Measles also weakens the immune system, leaving individuals more vulnerable to other infections for up to two years afterward. This “immune amnesia” may raise death rates beyond the initial illness, especially in areas with other widespread diseases, underscoring the urgency for sustained and comprehensive prevention strategies.
Healthcare providers, particularly primary care physicians, play a crucial role in increasing vaccination rates. They must engage parents in ongoing, respectful conversations, addressing fears and misinformation without judgment.
Children should receive routine MMR vaccines at 12 and 60 months of age, with early or accelerated doses administered when the exposure risk is high.
Refusing care to families who decline vaccines is not proven effective; instead, repeated, empathetic discussions can gradually change minds.
Public health efforts must also address the cultural, religious, and political influences behind vaccine hesitancy. Successful campaigns must consider community beliefs, as shown by an effective faith-led vaccination drive in India. This approach can inform local outreach efforts, such as those in Gaines County, where religious communities have low vaccination rates.
Without more decisive local and global action, communities remain vulnerable to measles and other preventable diseases, raising concerns about the possible return of endemic measles in the United States. The authors describe measles as a “canary in the coalmine,” signaling broader population vulnerability to vaccine-preventable diseases.