US Kindergarten Vaccination Rates Slip Below Herd Immunity Threshold as Exemptions Surge
Amidst rising measles cases and controversial executive orders, the Centers for Disease Control and Prevention released data indicating a continued decline in childhood immunisation rates and a sharp rise in non-medical exemptions.
The Centers for Disease Control and Prevention has released data for the 2025–2026 school year revealing a further decline in US kindergarten vaccination rates, with national coverage for the measles, mumps, and rubella (MMR) vaccine dropping to 92.4 per cent and the diphtheria, tetanus, and acellular pertussis (DTaP) vaccine falling to 92.0 per cent. Both figures sit below the 95 per cent threshold widely recognised as necessary to maintain herd immunity and prevent community outbreaks of vaccine-preventable diseases.
This marks a continued downward trend from the 2019–2020 school year, when national rates hovered around the 95 per cent mark. More than half of US states recorded decreases in coverage for MMR, DTaP, polio, and varicella vaccines compared to the previous year. Only 10 states—West Virginia, Connecticut, Maine, New York, Mississippi, Rhode Island, Maryland, Massachusetts, California, and New Mexico—maintained MMR vaccination rates at or above the critical 95 per cent level.
While vaccination coverage has slipped, the number of children granted exemptions from school vaccine requirements has risen more sharply. The non-medical exemption rate, which covers exemptions based on personal or religious beliefs, increased to 4 per cent from 3.2 per cent in the 2024–2025 school year. In contrast, medical exemptions have remained steady at 0.2 per cent over recent years.
The rise in non-medical exemptions is particularly significant as it directly impacts the achievable coverage rate for communities. When exemption rates exceed 5 per cent in a given location, the 95 per cent coverage target becomes mathematically impossible to reach. The number of states with exemption rates at or above 5 per cent has jumped from 14 in the 2023–2024 school year to 24 in the current cycle.
The data was released online without the full analysis or vetted publication typically found in the agency’s Morbidity and Mortality Weekly Report. This method of release follows the precedent set under Health Secretary Robert F. Kennedy Jr., who has overseen a departure from traditional analytical reporting. The CDC stated in a media release that the agency continues to encourage parents to discuss vaccination options with their doctors.
These findings emerge against a backdrop of rising vaccine-preventable diseases, with measles cases reaching a 34-year high and threatening the country’s elimination status. Concurrently, President Donald Trump and Health Secretary Kennedy announced an executive order to reduce the number of recommended vaccinations, a move described as lacking scientific basis and accompanied by the spread of misinformation regarding vaccine safety and efficacy.
