As measles spreads nationwide, fewer Minnesota kindergartners have herd immunity

Minnesota's kindergartners have fallen below the 95% herd immunity threshold for the MMR vaccine, with only 87% fully vaccinated this school year. The decline in vaccination rates has persisted since the onset of the COVID-19 pandemic, leading to an increase in nonmedical exemptions, which now account for 5. 7% of kindergartners. In 2025, the state has reported two measles cases, following a significant rise in cases in 2024. Only five counties met the herd immunity threshold, highlighting regional disparities in vaccine acceptance.

Wadena County has the lowest vaccination rate, with over 25% of kindergartners having nonmedical exemptions. The Minnesota Department of Health is concerned about the implications of these trends on public health and community safety. State officials are encouraging vaccination to protect children from infectious diseases. Health experts warn that without intervention, the risk of outbreaks will increase, particularly in areas with low vaccination rates.