US Faces Worst Measles Outbreak in Three Decades Amidst Declining Vaccination Rates

The United States is confronting its most severe measles outbreak in over three decades, with 1,288 confirmed cases reported across 39 states as of July 2025. This resurgence, which began in February in an under-vaccinated region of West Texas, has resulted in at least three deaths and numerous hospitalizations, primarily among unvaccinated children and adolescents.

Measles, a highly contagious viral disease, was declared eliminated in the U.S. in 2000 due to widespread vaccination efforts. However, declining vaccination rates have led to periodic resurgences, with the current outbreak being the most significant since elimination. The Centers for Disease Control and Prevention (CDC) reports that approximately 68% of recent cases have occurred in individuals under 20 years old, with 30% in children under 5 years and 38% in those aged 5 to 19 years. Thirteen percent of cases have resulted in hospitalization, with the highest hospitalization rate (23%) among children under 5 years.

Health experts attribute the resurgence to declining vaccination rates, partly fueled by misinformation. The CDC recommends that children receive two doses of the MMR (measles, mumps, and rubella) vaccine: the first at 12 through 15 months and the second at 4 through 6 years. Adults without evidence of immunity should also be vaccinated. Two doses of the MMR vaccine are 97% effective in preventing measles.

The federal response to the outbreak has faced criticism for delays and inadequate emphasis on vaccination. Some officials have downplayed the severity of the outbreak, and there have been reports of misinformation from public figures. The spread of misinformation has eroded public trust in vaccines and public health institutions, complicating efforts to control the outbreak.

The outbreak has placed additional strain on healthcare systems, particularly in under-resourced areas, highlighting disparities in healthcare access and infrastructure. Researchers warn that the U.S. is nearing a tipping point for the return of endemic measles, nearly 25 years after it was declared eradicated. Modeling estimates suggest that at current vaccination levels, measles could cause 851,300 cases over the next 25 years.

To prevent further spread, the CDC emphasizes the importance of vaccination and urges parents to ensure their children are vaccinated. Public health officials continue to monitor the situation closely and are working to address the factors contributing to the outbreak.