CDC Records Highest U.S. Measles Surge in 35 Years

By early November 2026 the Centers for Disease Control and Prevention (CDC) announced a startling figure: 5,182 confirmed measles cases across the United States. That number tops every tally the agency has produced since 1991, marking the biggest resurgence of the disease in three and a half decades.

What makes the spike especially unsettling is who’s falling ill. Children under five account for about 18 % of the cases, while those between five and 19 make up roughly 41 %. Put together, kids and teenagers represent almost 60 % of all infections – a sobering reminder that the disease still finds its easiest targets among the young.

Most of the illnesses – 4,993 to be precise – are linked to identifiable outbreaks, rather than isolated incidents. The pattern mirrors a worrying decline in vaccine coverage. In the 2019‑2020 school year, 95.2 % of kindergarteners were fully immunised against measles; by the 2025‑2026 year that figure had slipped to 92.4 %.

The death toll, though comparatively low, has become a point of contention. CDC data list four measles‑related deaths for 2026, yet Pennsylvania’s health department reports six fatalities and 1,487 cases within the state alone. The discrepancy stems from differing definitions: Pennsylvania counts “measles‑associated” deaths that occur within 30 days of symptom onset, unless another cause is clearly identified, while the CDC has been more cautious, especially after health secretary Robert F. Kennedy Jr. questioned the link in two recent cases.

Officials say they’re working with the Council of State and Territorial Epidemiologists to settle on a uniform definition for measles‑related deaths, a step that would align federal reporting with long‑standing World Health Organization practices.

Beyond the borders of the United States, measles is on the rise worldwide, often in pockets where vaccine skepticism or limited healthcare access prevails. Epidemiologists warn that an outbreak in one corner of the globe can quickly become a problem elsewhere, underscoring that immunisation is a shared, global responsibility.