U.S. Faces Largest Measles Outbreak in Five Years amid Declining Vaccination Rates

The United States is confronting its most severe measles outbreak in five years, with over 1,000 confirmed cases reported across 30 states as of June 2025. Health officials attribute this surge to declining vaccination rates and policy shifts affecting immunization practices.

Measles, a highly contagious viral disease, was declared eliminated in the U.S. in 2000. However, recent data indicates a troubling resurgence. The Centers for Disease Control and Prevention (CDC) reports that 97% of the 884 confirmed cases this year involved individuals who were unvaccinated or had unknown vaccination status. Notably, 11% of these cases resulted in hospitalization, and three deaths have been confirmed.

Vaccination rates among children have declined in recent years. During the 2023-2024 school year, the measles-mumps-rubella (MMR) vaccination coverage among kindergartners fell to 92.7%, down from 95.2% in 2019-2020. This decline is concerning, as a 95% vaccination rate is necessary to prevent outbreaks. Factors contributing to this trend include vaccine hesitancy fueled by misinformation and political influences.

The current outbreak has been particularly severe in close-knit communities with low vaccination rates. In Gaines County, Texas, a significant outbreak has been concentrated within a Mennonite community known for low immunization coverage. The county has one of the highest rates of vaccine opt-outs among children, with nearly 14% skipping a required vaccine in the prior school year. As of April 17, 2025, this outbreak accounted for 82% of the 800 measles cases reported nationwide.

Federal and state responses have varied. Health and Human Services Secretary Robert F. Kennedy Jr., known for his critical views on vaccines, has emphasized the importance of the MMR vaccine in preventing measles. In a statement, he expressed deep concern about the recent outbreak and highlighted the crucial role of vaccination in protecting individual children and contributing to community immunity. At the state level, Texas health officials have implemented a 21-day quarantine for exposed unvaccinated individuals but have not declared a state of emergency, citing that 90% of Texans are vaccinated.

The economic implications of the outbreak are significant. Each measles case incurs direct medical expenses averaging $10,000, excluding indirect costs like lost productivity. With outbreaks reported in multiple states, the national healthcare system faces a projected burden of hundreds of millions of dollars. Beyond healthcare, outbreaks disrupt workforce participation as parents stay home with sick children or quarantine measures limit business operations.

Public health experts warn that if vaccination rates continue to decline, measles could become endemic again within two decades. A recent study published in JAMA predicts that with current vaccination levels, measles could cause 851,300 cases over the next 25 years. A 10% drop in MMR vaccination could lead to 11.1 million cases. Even small increases in vaccination rates—about 5%—could prevent measles from becoming endemic again.

The 2025 measles outbreak serves as a stark reminder of the importance of maintaining high vaccination rates and combating misinformation. Addressing these challenges is crucial to prevent future outbreaks and protect public health.