DES MOINES, Iowa — Iowa’s low immunization rate for measles is causing concern for health officials following three confirmed cases in the state.

According to data from the Iowa Department of Health and Human Services, the immunization rate for 1 MMR (Measles, Mumps, and Rubella) for two-year-olds across the state is 84%.

Health officials recommend the vaccination rate to be at least 95% because of how contagious measles is. A 95% vaccination rate would mean communities reached herd immunity, and it would help prevent outbreaks.

The same data also shows that only 11 counties in the state meet or exceed the 95% threshold for 1 MMR in children under two. These include Winneshiek, Buena Vista, Humboldt, Wright, Grundy, Crawford, Shelby, Dallas, Madison, Page, and Clarke counties.

Additional data shows that for the 2024 – 2025 school year, 92.9% of K-12 students reportedly had two doses of the measles vaccine. This percentage continues to decrease, from 93.6% during the previous year and 95.6% in the 2020 – 2021 school year.

Dr. Nathan Boonstra is a pediatrician in Des Moines and the chair of Iowa Immunizes, the state’s immunization coalition. He said that the reasons why people are unvaccinated vary.

Some people aren’t vaccinated because of political reasons, and more people are now seeking religious exemptions. However, he also said that many vaccination rates decreased during the COVID pandemic because people were making fewer visits to the doctor, and some people might just not know the severity of measles.

“I don’t think people realize the real risk of measles. Yes, it was a disease every child used to get back before the vaccine came out. And what I think people don’t realize is that there was still, back then, a lot of pneumonia a lot of encephalitis or inflammation of the brain caused by measles, that measles damages the immune system when you catch it, and although a lot of people did okay with measles, some did not,” he said.

Since May, HHS has confirmed three cases of measles in Iowa. The latest case was announced last week in an unvaccinated child in Eastern Iowa.

The department also released a list of locations that the child visited while contagious, including a Costco and a Marshalls in Coralville and a Walmart in Iowa City.

Both Coralville and Iowa City are in Johnson County, which HHS data indicates has a 90% immunization rate for 1 MMR in children under two. While this vaccination rate is below the 95% threshold, it’s relatively higher compared to counties like Davis County in Southern Iowa, where the same data only shows a 41% immunization rate.

The second measles case also occurred in eastern Iowa in a vaccinated adult male, and the first case was reported in May in an unvaccinated adult female in central Iowa. HHS did not release specific information regarding the locations of these two cases.

According to Dr. Boonstra, where the cases are is what can cause larger outbreaks.

“We’ve seen measles from time to time in Iowa, every once in a while there’s a case, two cases or whatnot. The real concern is when is it going to be that measles hits one of these communities where immunizations are low? Because that is also something that’s more a matter of when rather than if,” he said.

According to HHS, measles is a highly contagious viral illness that is spread through the air when an infectious person coughs, sneezes, or breathes. Symptoms of measles include fever, cough, red/watery eyes, runny nose, and a rash. Two doses of the vaccine are administered. The first dose is recommended at 12 to 15 months of age, with a second dose at 4 to 6 years.

Dr. Boonstra said the vaccine is highly effective and provides immunity in about 97% of vaccinated individuals after two doses.