The United States has recorded 2,318 measles cases in 2026, marking the worst outbreak year since 1991 and surpassing last year's total of 2,289, the CDC reported. Major outbreaks are concentrated in South Carolina, which saw 997 cases, and Utah, where an ongoing outbreak has infected more than 700 people since June 2025.
New outbreaks have emerged in Arizona, Delaware, and Wyoming, while Pennsylvania reported 132 cases and Virginia 177. The CDC found that 93 percent of infected individuals were unvaccinated. National vaccination rates for kindergartners fell to 92.5 percent in the 2024-2025 school year, below the 95 percent threshold needed to prevent outbreaks.
The US eliminated local measles transmission in 2000, but a November 2026 meeting will determine whether the country has lost its elimination status. A West Texas outbreak included the first US measles deaths in over a decade.