In brief
The U.S. Centers for Disease Control and Prevention recorded 5,182 measles cases in 2026, the most since 1991. Almost 60 percent are children and teenagers, making vaccination gaps a key concern. Though the CDC lists four deaths, Pennsylvania cites six, fueling a dispute over how deaths linked to measles are counted.
The U.S. Centers for Disease Control and Prevention (CDC) announced today that it has recorded 5,182 cases of measles in 2026, the highest total reported in 35 years. Nearly 60% of the infections occurred in children and teenagers.
Children under five make up 18% of the cases, while those aged five to 19 account for 41%. The majority, 4,993 cases, are part of an ongoing outbreak.
Vaccination coverage among kindergarteners dropped from 95.2% in the 2019-2020 school year to 92.4% in the 2025-2026 school year, a decline that experts say has helped fuel the spike.
The CDC says four people have died from measles this year. However, state officials in Pennsylvania report six deaths and 1,487 cases, the most affected state in the outbreak.
Governor Josh Shapiro of Pennsylvania and U.S. Health Secretary Robert F. Kennedy Jr. disagree over the definition of a measles death. Pennsylvania counts “measles‑associated” deaths: a person confirmed with measles who dies within 30 days of symptoms unless the death is from an unrelated event. The CDC initially included those deaths in its national tally but later removed them after Kennedy questioned the classification.
This debate highlights the challenges of tracking disease outcomes when state and federal definitions differ. Public health officials say the current numbers underscore the need for higher vaccination rates, especially among schoolchildren.
