• Posted August 18, 2026

Kindergarten Vaccine Exemptions Hit Record High, New CDC Data Shows

A record share of U.S. kindergartners started school last year without at least one required vaccine, new federal data show.

Exemptions rose to 4.2% during the 2025-2026 school year, up from 3.6% a year earlier, according to the U.S. Centers for Disease Control and Prevention (CDC). That amounts to roughly 155,000 children.

Most of the jump came from families claiming nonmedical exemptions, The Washington Post reports. Twenty-four states now report exemption rates above 5%, the CDC said.

Nonmedical exemptions for school entrance tend to fall into two categories: religious and personal beliefs. Requirements vary from state to state.

Community immunity against measles requires more than 95% of susceptible people to be protected, so even small drops in coverage can fuel outbreaks, said Dr. Andrew Racine, president of the American Academy of Pediatrics.

"This risk is real," he said in a statement, adding that more than a quarter-million children began kindergarten last year without protection against measles, mumps and rubella (MMR).

Coverage slipped for every vaccine the agency tracks. This includes the MMR, DTaP (diphtheria, tetanus and acellular pertussis), varicella (chickenpox) and polio vaccines. 

Coverage for these shots dropped in more than half of states for the second year in a row.

About 280,000 kindergartners attended school last year without documentation that they had completed the two-dose MMR series.

The numbers arrive as measles spreads at its fastest pace in 35 years. The CDC had counted 2,566 confirmed cases as of Aug. 14, already more than the 2,289 logged during all of 2025. The agency notes that 93% of patients were unvaccinated or had an unknown vaccination status.

The data dovetails with a White House push to remake the childhood immunization schedule. 

President Donald Trump last week directed federal health officials to split the combined MMR shot into three separate vaccines and to spread childhood immunizations across more visits, The Post reports. 

Separate measles, mumps and rubella vaccines are not sold in the United States, and the CDC's own guidance says no published evidence shows a benefit to splitting the shot.

The agency did not mention the record exemption rate in the statement accompanying Monday's data. Instead of urging parents to vaccinate, it said it "continues to encourage parents to discuss vaccination options with their doctors."

States, not the federal government, generally set school vaccine requirements. 

As of Aug. 11, 30 states had stopped relying solely on federal guidance for their childhood vaccine recommendations, according to KFF, a health policy organization, The Post reports.

Two doses of MMR prevent about 97% of measles infections, the CDC says. 

More information

The American Academy of Pediatrics has more information about childhood immunizations. 

SOURCES: The Washington Post, Aug. 17, 2026; U.S. Centers for Disease Control and Prevention, Aug. 17, 2026