For the fourth consecutive year, the share of American kindergartners exempt from required school vaccinations has climbed to a new record — and the geographic clusters of unvaccinated children now correspond almost perfectly with the locations of the nation's most active measles outbreaks in 2026.
CDC data confirmed that 3.6% of kindergartners in the 2024–25 school year had at least one vaccine exemption, up from 3.3% the previous year. That percentage translates to approximately 138,000 children entering the school system without documented vaccination against one or more diseases for which they are otherwise required to be immunized. The vast majority of those exemptions are nonmedical — granted for personal or religious reasons rather than genuine contraindications.
