Measles, a disease declared eliminated in the United States in 2000, is making an alarming comeback. A combination of factors, including declining vaccination rates and increased global travel, has led to significant outbreaks across the country. Between 2024 and 2025, more than a dozen states have reported a surge in cases, raising serious public health concerns.
This guide provides a detailed look at the 15 states most affected by the recent spread of measles, exploring the number of cases in each state. We'll examine the contributing factors behind the outbreaks and the local responses to this public health challenge. Understanding the situation on the ground is the first step toward protecting our communities from this highly contagious, yet preventable, disease.
A Resurgence of a Preventable Disease
According to the Centers for Disease Control and Prevention (CDC), as of November 2025, there have been over 1,753 confirmed measles cases in the United States, which is a dramatic increase from just 59 cases in 2023 and 285 in 2024. A staggering 92% of these cases involved individuals who were either unvaccinated or had unknown vaccination status. These numbers highlight a critical vulnerability in our nation's public health defenses.
The outbreaks are not isolated incidents but are often linked, spreading through communities with low vaccination coverage. When the vaccination rate for the measles, mumps, and rubella (MMR) vaccine drops below the 95% threshold needed for community immunity (also known as herd immunity), the virus can spread quickly. Let's take a closer look at the states at the center of this resurgence.
States with Major Measles Outbreaks
The following states are ranked highest in the number of measles cases over the past two years:
1. Texas – 803 cases
Texas has emerged as the epicenter of the measles resurgence, reporting a staggering 803 cases between 2024 and 2025. This explosion in numbers is tied to several large, interconnected outbreaks, primarily concentrated in communities with low MMR vaccination rates. Public health officials have pointed to pockets of vaccine hesitancy, fueled by misinformation, as a significant driver of the spread. The state's large and mobile population has also contributed to the rapid transmission of the virus across different counties, making containment efforts particularly challenging.
The Texas Department of State Health Services (DSHS) has been working tirelessly to manage the outbreaks. Their response has included launching extensive public awareness campaigns to promote vaccination, setting up free immunization clinics in hard-hit areas, and conducting rigorous contact tracing to identify and quarantine exposed individuals. Despite these efforts, the sheer volume of cases has strained local health departments, underscoring the critical importance of high vaccination coverage as the first line of defense against this highly contagious virus.
2. Arizona – 133 cases
Arizona is grappling with a significant outbreak of 133 measles cases, a number that has put a major strain on its public health system. Investigations have traced many of the initial cases to international travel, with the virus then spreading rapidly within close-knit communities where vaccination rates are below the recommended 95%. The state's diverse geography, which includes both dense urban centers and remote rural areas, has complicated response efforts, making it difficult to reach all populations with timely information and vaccination services.
In response, the Arizona Department of Health Services (ADHS) has focused on targeted outreach and education. They have partnered with community leaders, schools, and healthcare providers to address vaccine hesitancy and dispel myths about the MMR vaccine. Mobile vaccination units have been deployed to underserved communities to improve access to immunizations. The state's experience serves as a powerful reminder that even a few imported cases can ignite a large outbreak when community immunity is compromised.
3. New Mexico – 100 cases
New Mexico has recorded 100 measles cases, a number that has alarmed health officials in a state with a mix of urban and sparsely populated rural regions. The outbreak has been characterized by rapid transmission within households and community settings, such as schools and childcare centers. Lower-than-ideal vaccination rates in several counties have created a fertile ground for the virus to spread. The New Mexico Department of Health (NMDOH) has noted that many of the cases involve children whose parents opted for non-medical exemptions to school-required vaccinations.
The state's response has been swift and multifaceted. The NMDOH has issued public health alerts, urging residents to check their vaccination status and get immunized if they are not protected. They have also worked closely with schools to enforce vaccination requirements and provide educational materials to parents. The outbreak has sparked a broader conversation in New Mexico about the importance of community immunity and the public health risks associated with vaccine refusal.
4. Kansas – 91 cases
Kansas is currently managing a significant outbreak with 91 confirmed measles cases. The spread has been particularly aggressive in several counties where MMR vaccination coverage has fallen below the protective threshold. Health investigators have linked the outbreak to multiple points of introduction, including international travelers and domestic travel from other affected states. Once introduced, the virus found a foothold in communities where clusters of unvaccinated individuals live in close proximity.
The Kansas Department of Health and Environment (KDHE) has implemented a robust response plan focused on containment and prevention. This includes aggressive contact tracing to quickly identify those exposed and extensive public messaging campaigns emphasizing the safety and effectiveness of the MMR vaccine. The state has also organized community vaccination clinics to make it easier for families to get their children up to date on their immunizations. The situation in Kansas highlights how quickly measles can take hold and spread when vaccination rates dip.
5. Utah – 84 cases
With 84 measles cases, Utah is facing one of its most significant public health challenges in recent years. The outbreak has been largely concentrated in a few counties with notably low vaccination rates. Health officials have observed that a high number of personal belief exemptions from school immunization requirements have contributed to the state's vulnerability. The virus has spread rapidly through social and family networks, affecting a large number of children and young adults who were not vaccinated.
The Utah Department of Health and Human Services has responded by providing clear, fact-based information to the public about the dangers of measles and the importance of vaccination. They have collaborated with local healthcare providers to ensure an adequate supply of the MMR vaccine and have been working to track the spread of the virus meticulously. The outbreak has reignited public debate in Utah over vaccination policies and the balance between individual choice and community health.
6. South Carolina – 52 cases
South Carolina has reported 52 cases of measles, a significant spike for the state. The outbreak is primarily concentrated in a handful of communities where vaccination coverage has been historically low. Public health officials have noted that the spread has been facilitated by gatherings and close community contact, allowing the highly contagious virus to move quickly among unvaccinated individuals. Many of the initial cases were linked to a single introduction from an infected traveler, demonstrating how easily the virus can be imported.
The South Carolina Department of Public Health has been proactive in its response, issuing guidance to healthcare providers and the public about recognizing measles symptoms and preventing further spread. They have emphasized the importance of the two-dose MMR vaccine series and have been working to identify and notify anyone who may have been exposed. The outbreak serves as a stark warning about the need for high community-wide vaccination rates to prevent a preventable disease from gaining a foothold.
7. Ohio – 39 cases
Ohio is contending with an outbreak of 39 measles cases, a concerning number that has put health departments on high alert. The majority of these cases have occurred in children who were not vaccinated against the virus. The Ohio Department of Health has traced the outbreak to several clusters, often originating within families or community groups with shared beliefs about vaccine hesitancy. This pattern highlights how localized pockets of low immunization can drive a larger public health crisis.
In response, Ohio health officials have been focused on a "back-to-basics" public health approach: vaccination, education, and containment. They have been working with local partners to increase access to the MMR vaccine and to provide accurate information to parents who may have concerns. The state's experience in 2022 with a large outbreak in the central region provided valuable lessons that are being applied to the current situation, emphasizing the need for a rapid and coordinated response.
8. Wisconsin – 36 cases
Wisconsin has confirmed 36 measles cases, a number that reflects a troubling trend of rising vaccine-preventable diseases in the state. Health officials have noted that a significant portion of the cases are among school-aged children in areas with higher-than-average rates of vaccination waivers. The outbreak has been linked to community transmission, with the virus spreading through schools and public spaces, posing a risk to infants too young to be vaccinated and other vulnerable individuals.
The Wisconsin Department of Health Services has mobilized to control the spread by promoting vaccination and educating the public on the seriousness of measles. They have stressed that the MMR vaccine is safe and highly effective, and have urged parents to follow the recommended immunization schedule. The outbreak is a critical reminder that maintaining high vaccination rates across all communities is essential to prevent the return of diseases that were once nearly forgotten.
9. North Dakota – 36 cases
North Dakota is also managing an outbreak of 36 measles cases. This is a significant number for a state with a relatively small population, and it has put a considerable strain on local public health resources. The cases have been clustered in specific communities, often linked by social networks, where vaccination rates have declined. The North Dakota Department of Health and Human Services has indicated that a lack of vaccination is the primary factor driving this outbreak.
The state's response has focused on identifying cases early and implementing control measures to limit transmission. This includes isolating infected individuals and encouraging vaccination for those who have been exposed but are not yet showing symptoms. Public health messages have been widely disseminated to inform residents about the risks of measles and the proven benefits of the MMR vaccine.
10. Montana – 32 cases
With 32 confirmed cases, Montana is facing a challenging public health situation. The state's rural landscape and independent-minded culture have sometimes been associated with lower vaccination rates in certain areas, creating vulnerabilities for outbreaks. The current spread has been linked to both travel-related introductions and subsequent community transmission. The cases have been reported across several counties, indicating that the virus is not contained to a single location.
Montana's Department of Public Health and Human Services has been working with local health departments to manage the outbreak. Their efforts include contact tracing, providing guidance on quarantine measures, and launching a public information campaign to encourage vaccination. The outbreak underscores the fact that no state is immune to the threat of measles, especially when pockets of under-vaccination exist.
11. Colorado – 31 cases
Colorado has reported 31 measles cases, a number that has prompted a strong public health response. The state has a history of contending with vaccine hesitancy, and some communities have immunization rates that fall short of the 95% target. The current outbreak has highlighted these vulnerabilities, with cases spreading among unvaccinated individuals who were exposed in public settings.
The Colorado Department of Public Health & Environment is leading the response, focusing on communication and vaccination. They are working to debunk misinformation about the MMR vaccine and provide clear, evidence-based reasons for immunization. The state is also ensuring that healthcare providers are prepared to identify and report suspected measles cases quickly to prevent further transmission.
12. Michigan – 28 cases
Michigan is currently managing an outbreak of 28 measles cases. This resurgence is a cause for concern in a state that has worked hard to improve its vaccination rates in recent years. The cases have appeared in several clusters, often starting within a household and then spreading to the broader community. The Michigan Department of Health and Human Services has emphasized that the overwhelming majority of those infected were unvaccinated.
The state's response has been to aggressively track the virus and promote vaccination as the most effective tool for prevention. Public health officials are working with schools, childcare centers, and community organizations to share information and host vaccination clinics. The outbreak serves as a reminder that vigilance is required to maintain community immunity and protect against preventable diseases.
13. Minnesota – 24 cases
Minnesota has confirmed 24 measles cases, bringing back memories of a large outbreak in 2017 that was centered in a community with low vaccination rates. The current situation shows similar patterns, with cases concentrated among unvaccinated children. The Minnesota Department of Health has been transparent about the challenges posed by vaccine hesitancy and has been working to build trust with affected communities.
The state's strategy involves a combination of culturally sensitive outreach, education, and accessible vaccination services. Health officials are partnering with community leaders to deliver accurate information about the MMR vaccine and address specific concerns. The ongoing effort in Minnesota highlights the importance of sustained community engagement in public health.
14. California – 22 cases
California, a state that tightened its school vaccination laws after a major measles outbreak at Disneyland in 2014-2015, is now reporting 22 cases. While this number is lower than in many other states, it is still a cause for concern. The cases have been scattered across the state and are mostly linked to international travel. The state's strict vaccination laws have likely prevented a much larger outbreak, but the new cases show that no place is entirely safe from imported viruses.
The California Department of Public Health continues to monitor the situation closely and advises residents to ensure they are up to date on their MMR vaccine, especially before traveling abroad. The state's experience demonstrates that strong public health policies are effective but must be paired with ongoing public awareness and vigilance.
15. Oklahoma – 17 cases
Oklahoma has reported 17 measles cases, a number that is straining local health resources. The outbreak has been linked to clusters of unvaccinated individuals, with transmission occurring in community settings. The Oklahoma State Department of Health is working to contain the spread by providing guidance on isolation and quarantine, as well as by promoting the MMR vaccine.
The state is focusing its efforts on educating the public about the dangers of measles, which can lead to serious complications like pneumonia and encephalitis. By highlighting the protective power of the vaccine, health officials hope to increase immunization rates and stop the outbreak from growing larger.
Now What?
The measles outbreaks of 2024 and 2025 are a clear and urgent wake-up call. They demonstrate that the elimination of a disease is not permanent and that public health achievements can be undone. The single most effective tool we have to fight this resurgence is the safe and proven MMR vaccine. Protecting ourselves, our families, and our communities depends on maintaining high vaccination rates to ensure strong community immunity.
