The United States is currently grappling with its worst measles epidemic of the 21st century, with 1,277 confirmed cases reported across 40 states since the beginning of 2025, according to the Centers for Disease Control and Prevention (CDC). This surge has already surpassed the previous high of 1,282 cases reported in 2019, and health officials are warning of further escalation if vaccination rates don’t improve.
Health authorities attribute the surge to declining childhood immunization rates, fueled by vaccine misinformation and pandemic-era disruptions in routine healthcare. Particularly concerning is the spread in communities with low vaccination coverage, where herd immunity has broken down, allowing the highly contagious virus to spread rapidly.
Measles is not a benign paediatric sickness, according to CDC immunologist Dr. Rochelle Fields, who also noted that it can cause serious side effects like pneumonia, encephalitis, and even death. “This outbreak serves as a reminder of what occurs when vaccination campaigns are put on hold,” she said. Most cases reported involved unvaccinated individuals or those with unknown vaccination histories.
Federal and state health departments are now ramping up emergency vaccination campaigns, outreach in vulnerable communities, and enforcing school-entry immunization requirements. Parents are urged to verify their children’s immunization status immediately. The CDC warns that the outbreak could worsen in the fall if preventive measures aren’t widely adopted.
