DES MOINES, Iowa — State data shows that the number of under- and unvaccinated students in Iowa continues to rise, and doctors are raising concerns.

According to data from the Iowa Health and Human Services, during the 2014 to 2015 school year, 4.4 percent of Iowa students were under- or unvaccinated. That was the same percentage in the 2020 to 2021 school year.

However, the number of under- and unvaccinated students started to tick upwards every year since. The audit for this school year hasn’t been released yet, but during the 2024 to 2025 school year, 7.1 percent of students were under- or unvaccinated.

“To keep these diseases from being able to easily spread from person to person, we need immunization rates to be above a certain level. Those levels are a little different for every vaccine, but if we don’t keep those vaccination rates up, that greatly increases the risk of outbreaks,” said Dr. Nathan Boonstra, a pediatrician in Des Moines who also chairs the state’s vaccine coalition, Iowa Immunizes.

There are vaccines that are required for students. Each has different requirements as far as when they should be administered and how many doses are needed. These vaccines include:

• Diphtheria, Tetanus, Pertussis (DTaP)
• Polio
• Measles, Mumps, Rubella (MMR)
• Hepatitis B
• Varicella (Chickenpox)
• Meningococcal Vaccine

Boonstra said decreases in the MMR and Hepatitis B vaccines are the main concerns for doctors today.

This comes after there were eight confirmed cases of Measles in the state this year as of July 2025. Iowa’s low immunization rate for the MMR vaccine played a role, according to doctors.

Some people, however, are unable to get vaccinated. In Iowa, there are two ways to be exempt from the vaccine requirement: medical and religious exemptions.

Boonstra said another concerning vaccine trend is the growing number of religious exemptions.

In the 2019 to 2020 school year, two percent of students had religious exemptions, but in the last school year, that number rose to 3.6 percent.

“In a school setting, you just have a lot of kids in a relatively small amount of space and a greatly increased chance of an outbreak happening if enough not-immune kids are exposed to measles or another such disease. So, it’s even more important when we talk about school setting. That’s why these vaccines are recommended and required,” Boonstra said.

He encourages parents to talk to their child’s medical care providers about any questions regarding vaccine hesitancy.

The Iowa School Immunization Audit Data for the 2025-2026 school year is expected to be released later in the school year.