Measles 2025: Looking Back and Moving Forward

It should not have happened, and yet it did. We know better, but we continue to make the same mistakes. Measles (rubeola), the most contagious virus infecting humans (FIGURE 1), remains endemic in many parts of the world. Thanks to highly effective measles mumps rubella (MMR) vaccines, the virus was declared eliminated in the US in 2000.¹ Yet as of August, more than 1300 US cases have been reported thus far in 2025,¹ with larger outbreaks in Ontario, Canada, and Chihuahua, Mexico.² Most of the US cases (~ 96%) involve unvaccinated children and young adults—and at least 3 have died. The rise in cases from 2024 highlights the growing threat of declining vaccination rates, travel, and community spread in undervaccinated populations.

There are many drivers for this situation, including:

• questioning the need for ongoing vaccination (among the public and some government officials and health care professionals);

• ongoing circulation of mis- and disinformation about the safety and effectiveness of vaccination (writ large);

• mistrust of public health, health authorities; and

• vaccine fatigue emerging from the COVID-19 pandemic.

Prevention: MMR Vaccine

Measles vaccination is the only available tool to prevent measles infection and its potential complications. Vaccination has been recommended in the US since the 1960s.^3,4 Currently in the US, 2 approved MMR vaccines are available, and vaccination is recommended for nearly all children. The standard schedule is for a first dose at 12 to 15 months and a second dose at 4 to 6 years, but the second dose of MMR vaccine can be administered as soon as 1 month after the first dose.^3,4 MMR vaccination is highly effective, with 1 dose resulting in protection of approximately 93% of those vaccinated, and with 2 doses, this increases to approximately 97%.^3,4 The MMR vaccine may be given as early as 6 months to prevent disease in unvaccinated persons in an outbreak situation or before international travel, but doses given before 1 year do not provide predictable long-term immunity. Because of this, 2 doses after 1 year are recommended for persons who were vaccinated before their first birthday. MMR vaccination is recommended for adults born since 1957 who do not know whether they have been vaccinated or are immune. The best defense against measles is vaccination, and if individuals are not sure of their immunity or vaccination status, it is safe to get a measles vaccine, unless contraindicated. MMR is a live attenuated vaccine and should not be given to persons with moderate to severe immune suppression or during pregnancy.^3,4

Measles Treatment

There are no specific antiviral drugs approved to treat measles. The goal of medical care is to relieve symptoms and address complications such as bacterial infections that can be serious or even deadly. Severe measles cases among children who are hospitalized may be managed with vitamin A, but this should only be done under the supervision of a health care professional because high-dose vitamin A has potential toxicity and needs to be closely monitored. Vitamin A is not a cure, and it does not prevent measles—only vaccination can do that.⁵

History of Measles Vaccination

Before the vaccine became available in the 1960s, measles infected nearly every child by their teen years and caused millions of deaths, mostly in children, worldwide each year.⁶ With improved sanitation, nutrition, and living conditions and the widespread availability of antibiotics for treatment of secondary infections in the US and Europe, measles became much less deadly. Hundreds of thousands of infections continued to occur annually in the US and Europe, but deaths became far less common than they were in countries that did not have these resources. As a result of the improvements in measles outcomes in the US, there was some debate in the 1970s about the need for a universal immunization campaign. Many people thought of measles as a common disease of childhood to be “lived with.” This sentiment did not take into account the deaths, immune system damage (which resulted in many secondary bacterial infections such as pneumonia and ear infections), and the rare but unpredictable and devastating late neurologic complications from measles.⁷ Most persons born in the US before 1957 have lifelong immunity from childhood infection. Measles was endemic in the US before this time, and most were infected during childhood. The first measles vaccines (one inactivated and another live attenuated measles vaccine) became available in the US in 1963.⁶ The inactivated vaccine was effective but did not result in long-lasting immunity. Early live attenuated vaccines were much more reactogenic.⁶ Further vaccine development and virus strain attenuation resulted in safer vaccines and ultimately led to the development and introduction of the combined MMR vaccine. With the widespread introduction of the measles vaccine in the US, the incidence of disease fell rapidly, but disease elimination in the US took much longer. Public uptake of the vaccine remained below goals due to cost and low demand. It was not until school vaccination requirements and permanent federal funding were established that the US was able to declare measles eliminated (defined as the absence of continuous disease transmission for 12 months or more in a specific geographic area).⁸

Ongoing Efforts to Eliminate Measles

Global efforts to eliminate measles are ongoing,⁹ but measles continues to circulate widely in many countries. Measles vaccination—like many preventive services—declined during the COVID-19 pandemic, leading to a surge in cases and large outbreaks in multiple countries. From 2022 to 2023, estimated measles cases increased by a reported 20%. Although international and US vaccination trends are similar, the gap between current immunization rates and the threshold needed for community protection is much greater in many other countries. In the US, most measles outbreaks stem from imported cases and involve unvaccinated or undervaccinated travelers. Unfortunately, vaccination rates for populations at the country, state, or even county level may greatly underestimate the risk that lies in communities, neighborhoods, and other pockets where immunization is not the norm.¹⁰ We have a great challenge in front of us to stem the current outbreaks and to prevent them going forward. To reliably prevent measles circulation in communities, we need to achieve and maintain vaccination rates near 95%.⁸

How to Build Confidence in Measles Vaccination

If we are to reach families and individuals who are unvaccinated and undervaccinated, we need to start by developing trusting individual relationships, followed by listening to concerns and assuring that we share the goals of protecting the health and safety of these families. Building on common goals, we can then explore and address motivations, understand fears, and ultimately get children and families immunized. This is not a problem that will be solved overnight, but it can be achieved over time. Beyond efforts focused on individual families, building long-term relationships with community, religious, and social group leaders can help reestablish vaccination as a social norm and rebuild trust in the long run. On a larger scale, breaking through the waves of mis- and disinformation and restoring confidence in public health will require action on multiple fronts. Although collaboration with media and social media platforms and the efforts of tenacious individuals to address false claims online are important, they have limits. The “whack a mole” metaphor is accurate. Even so, health care professionals can contribute by participating in media interviews and sharing accurate, science-based content on social media. Long term, we as a society must do more to equip future generations to navigate misinformation. Strengthening education in media literacy, critical thinking, and the science behind vaccines could help prevent similar crises in the future.

An End in Sight?

In recent weeks, identified measles cases in the US appear to be slowing, but we cannot step back from our efforts. MMR vaccination remains the only evidence-based way to prevent measles and help protect patients and families. As health care professionals, we must continue having honest, informed conversations with patients and families—listening to concerns and offering strong, clear recommendations for MMR and other appropriate vaccines. It is also important to dispel myths and reiterate, to some families, that vitamins do not prevent measles. As summer travel increases, we should ask about travel plans and recommend MMR vaccination for unvaccinated individuals 6 months of age and older. And we need to remain vigilant in looking for that next case.

To learn more about measles, visit NFID's site.

References

1. Measles cases and outbreaks. Centers for Disease Control and Prevention. June 6, 2025. Accessed June 12, 2025. https://www.cdc.gov/measles/data-research/index.html

2. Measles – region of the Americas. World Health Organization. April 28, 2025. Accessed June 5, 2025. https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON565

3. Measles vaccine recommendations. Centers for Disease Control and Prevention. September 20, 2024. Accessed June 5, 2025. https://www.cdc.gov/measles/hcp/vaccine-considerations/index.html

4. Measles vaccination. Centers for Disease Control and Prevention. January 17, 2025. Accessed June 5, 2025. https://www.cdc.gov/measles/vaccines/index.html

5.Vitamin A for the Management of Measles in the United States. National Foundation for Infectious Diseases. March 2020. Accessed June 5, 2025. https://www.nfid.org/resource/vitamin-a-for-the-management-of-measles-in-the-us/

6. Hendriks J, Blume S. Measles vaccination before the measles-mumps-rubella vaccine. Am J Public Health. 2013;103(8):1393-1401. doi:10.2105/AJPH.2012.301075

7. Bester JC. Measles and measles vaccination: a review. JAMA Pediatr. 2016;170(12):1209-1215. doi:10.1001/jamapediatrics.2016.1787

8. Why it took so long to eliminate measles. History. Updated May 27, 2025. Accessed June 5, 2025. https://www.history.com/articles/measles-vaccine-disease

9. Minta AA, Ferrari M, Antoni S, et al. Progress toward measles elimination — worldwide, 2000-2023. MMWR Morb Mortal Wkly Rep. 2024;73(45):1036-1042. doi:10.15585/mmwr.mm7345a4

10. Dong E, Saiyed S, Nearchou A, Okura Y, Gardner LM. Trends in county-level MMR vaccination coverage in children in the United States. JAMA. Published online June 2, 2025. doi:10.1001/jama.2025.8952