The United States is experiencing its worst measles outbreak in 35 years, with federal health officials confirming that case counts have now broken records for two years running. According to the Centers for Disease Control and Prevention, 2,318 confirmed measles cases had been logged by July 23, already surpassing the 2,289 cases recorded for all of 2025, which itself had been the highest annual total since 1991. With more than five months still left in the year, health experts warn the final number could climb significantly higher.
The resurgence marks a dramatic reversal for a disease the country had declared eliminated in 2000, following decades of successful immunization campaigns. Public health specialists say the comeback of measles is closely tied to a steady erosion of childhood vaccination coverage.
National vaccination rates among kindergartners fell to about 92.5 percent in the 2024-2025 school year, down from 92.7 percent the year before and well below the 95.2 percent recorded before the COVID-19 pandemic. Because measles is one of the most contagious diseases known, a community vaccination rate of roughly 95 percent is generally considered necessary to prevent sustained transmission once the virus is introduced.
Outbreaks tied to the current surge in measles have appeared across numerous states, including South Carolina, Arizona, Utah, Virginia, Pennsylvania, Delaware and Wyoming. South Carolina has reported the largest cluster, with nearly a thousand cases logged during its outbreak, though officials caution the real figure is likely higher because reported totals tend to undercount actual infections. In Virginia, an outbreak that began in May appears to be easing, aided partly by health workers going door to door in affected communities to encourage immunization and answer residents’ concerns.
CDC data show that the vast majority of this year’s measles patients, roughly 93 percent, were unvaccinated or had unknown vaccination status, while only a small fraction of cases occurred among people who had received one or both recommended doses of the measles, mumps and rubella vaccine. Children and teenagers make up most of those infected, and roughly one in ten children under age five who contracted measles this year required hospitalization. Three deaths linked to measles were reported in 2025, the first fatalities from the disease in the country since 2015.
Health officials and former public health leaders have described the milestone as an alarming setback. Some experts believe the country is now at risk of losing the elimination status it earned twenty-five years ago, a designation that requires no continuous domestic transmission of the virus for more than a year. A joint review of the elimination status of both the United States and Mexico is expected later this year. Contributing factors cited by specialists include declining public trust in health institutions, inconsistent messaging from federal agencies, and growing skepticism toward routine childhood immunizations, even as scientific evidence continues to affirm the vaccine’s safety and effectiveness.
Despite the politically charged debate surrounding vaccination policy, health authorities continue to stress that maintaining high immunization coverage remains the most reliable defense against further measles outbreaks. Officials note that pockets of unvaccinated people, even within states that otherwise report strong overall coverage, can allow the virus to take hold and spread quickly once it arrives. As the year continues, monitoring agencies say they will keep tracking new measles cases weekly, with the expectation that the national total will keep climbing before 2026 draws to a close.
