As Florida moves to lift vaccine mandates, do Minnesota kindergartners have ‘herd immunity’?

Fewer Minnesota kindergartners are fully vaccinated against measles, Minnesota Department of Health data shows, falling well short of the 95% “herd immunity” target set by state officials and public health professionals to prevent community transmission.

About 87% of Minnesota’s kindergartners had both doses of the mandated MMR vaccine, which protects against measles, mumps and rubella, last school year, continuing a downward trend.

Meanwhile, tensions over vaccine policy reportedly led to the firing of Centers for Disease Control and Prevention Director Susan Monarez, in the position only a month, as U.S. Health and Human Services Secretary Robert F. Kennedy, Jr. moves to remake the guidance. Four other CDC officials resigned shortly thereafter.

Kennedy testifies before the U.S. Senate Thursday, and is likely to face questions on vaccine policy.

In Florida, the surgeon general announced on Wednesday that the state is “working to end” all vaccine mandates for children and adults alike.

Minnesota has reported five measles cases so far in 2025, following 70 last year — the highest case count since a 2017 outbreak.

Nationally, more than 1,400 measles cases have been confirmed across more than 40 states this year, according to the CDC. Outbreaks have been especially concentrated in Texas, where two unvaccinated children have died.

The MMR vaccine requires two doses and is one of five vaccines that are state-mandated for incoming kindergartners before starting school. The other mandated vaccines protect against diphtheria, tetanus, whooping cough (pertussis), polio, hepatitis B, and chicken pox (varicella).

There are similar requirements for child care centers, early learning centers and older children.

Though vaccination rates for all five have plummeted, MMR has fallen the most for kindergartners.

Statewide, Minnesota kindergartners haven’t met the 95% herd immunity threshold in at least a decade, but the MMR vaccination rate has also been on a steady decline since the onset of the COVID-19 pandemic in 2020.

The share of students who get a medical exemption — usually meaning they are allergic or immunocompromised in some way — has been a consistent sliver of the unvaccinated population.

Those 5.7% of kindergartners alone — amounting to about 3,600 children — put Minnesota’s kindergarteners below herd immunity, but there’s another muddier category: Partial vaccination.

“Partially vaccinated” kindergartners include students who have either zero or one dose of the MMR vaccine instead of the required two, and who lack a notarized exemption. It can also mean parents simply haven’t submitted records to the school. The share of kindergartners in this fuzzy category has also risen since 2020.

Some regions of the state have seen bigger changes in acceptance of MMR vaccine than others.

In 2014, more than half of Minnesota’s 87 counties met the herd immunity threshold. That started to taper slightly even before the pandemic, but a rapid increase in vaccine hesitancy is evident.

Last school year, there were only five counties whose kindergartners met the threshold: Pennington, Traverse, Yellow Medicine, Cottonwood and Watonwan.

Wadena County, with Hwy. 10 running through its southwest corner and Menahga in the north, has the state’s lowest vaccination rate — and the highest share of kindergartners with nonmedical exemptions. Of 206 enrolled kindergartners across four school districts last school year, more than one-quarter had a nonmedical exemption.

Clearwater County’s vaccination rate for its 94 kindergartners is nearly as low, but they don’t have a high share of exemptions — instead, they have the highest share of kids in that “partially vaccinated” category.

Data for the current school year is typically released in the spring.

Charter schools, which are counted as their own district, have a lower vaccination rate generally than traditional public schools, though both have dropped at about the same rate. In this school year, traditional public school districts had a full vaccination rate slightly higher than the state average at about 87%. Charter schools, by contrast, have about 77% of kindergartners with full MMR vaccination.

Some individual school districts have also experienced steep drops since 2014. Higher Ground Academy, Menahga, and Stride Academy Charter School in St. Cloud have seen rates fall by more than 30 percentage points.

In Menahga, the biggest district in Wadena County, more than half of kindergartners have nonmedical exemptions; the same is true for nearly a quarter of the kindergartners in Dassel-Cokato.

Among the 10 districts with the largest declines, four are charter schools. In most cases, the drop is driven by high partial vaccination rates.

Some school districts and charter schools are seeing significant progress, too.

The Dilworth-Glyndon-Felton district made the largest improvement, with a 19 percentage point increase. Of other districts with big improvements, most were below 80% in 2014 but have since caught up to the statewide rate.

Search below for your school’s MMR full-vaccination rate and nonmedical exemption rate for kindergartners in the 2024-25 school year.