Overview
- Health authorities have logged 2,318 measles cases so far this year, a total reached in July that is the highest since 1989–1991.
- About 93 percent of reported infections occurred in people who were unvaccinated, and two doses of MMR provide roughly 97 percent protection.
- Children and teens account for the bulk of cases with 69 percent aged 0–19 and roughly one-fifth under five years old.
- The virus has spread to roughly 45 states with 35 outbreaks recorded and a single South Carolina cluster sickening nearly 1,000 people since October 2025.
- Public-health officials point to falling kindergarten MMR coverage — about 92.5 percent nationally and under 90 percent in 16 states — plus vaccine skepticism after federal advisory changes as the main threats to maintaining elimination, raising the risk of more outbreaks and strain on local health services.