Children in Montana get vaccinated at a lower rate than those in the nation as a whole — just 62 percent of those in the Treasure State complete the recommended vaccination series compared to 71 percent nationally, according to the University of Montana.
A new study from the Missoula flagship looks at why.
Sophia Newcomer, lead researcher at UM on the study conducted in partnership with the Montana Department of Public Health and Human Services, said the team wanted to know if under-vaccination was due to accessibility or to parental hesitation, reports the Daily Montanan.
“We found out the answer is both,” Newcomer said Monday.
But the researchers evaluated the data with a map of Montana.
“If we can figure out what areas in Montana are having each of those types of issues, we can then work on programs and interventions to address the root causes of under-vaccination,” said Newcomer, with the UM Center for Population Health Research.
In its report on the study, UM said the project is the first “spatial scan analysis” to identify clusters of under-vaccinated children and evaluate whether the reason is due to social or geographic barriers. UM noted the study was published in the American Journal of Preventive Medicine and cited the low vaccination rate in Montana, also noting just 38 percent of children receive vaccinations on time.
A second study is still preliminary and will be submitted for publication this summer, and the map identifying “hot spots” hasn’t been peer reviewed and isn’t public, Newcomer said. However, an analysis of the hot spots shows the reasons for under-vaccination differ by location.
“The barriers to timely childhood vaccination look very different when you’re looking at western or eastern Montana,” said Newcomer, assistant professor with the UM School of Public and Community Health Sciences.
The Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices recommends that by age 2, children receive vaccines for diphtheria, tetanus and pertussis; polio; measles, mumps and rubella; hepatitis B; varicella; Heamophilous influenzae type b; and pneumococcal disease, according to the report from UM.
On the western side of the state, the hurdle to vaccination is likely parental hesitancy, Newcomer said. In that case, the research shows pockets where children have some of the recommended vaccines by 2 years old, but not all of the ones in the series, indicating skepticism. Also, she said, children may have their vaccinations spread out in a way that’s not recommended. Generally, she said, the finding in this area tracks with the already known high prevalence of religious exemptions for vaccinations for children in public schools.
On the eastern side of the state? Newcomer said the data indicate children aren’t getting all their vaccinations because of barriers to accessing immunization services. In those cases, children may have started taking all their vaccines, but may not have finished the series.
The different findings point to the need for different approaches to move the dial.
“Fundamentally, solutions to address those two problems are very different,” Newcomer said.
Where barriers exist, the fix might be making sure enough immunization providers are available, and also making sure families know they need to return to complete the series, she said. Where parental hesitancy exists, she said, solutions might involve working with nurses and providers on effective conversations and social media programs that build trust around vaccines.
In the UM report, Rain Freeman, UM’s epidemiology specialist and the project’s data manager, said national Vaccines for Children Program data showed a substantial decrease in routine, pediatric vaccine orders at the beginning of the pandemic. She said making sure children are vaccinated on time is crucial to preventing diseases and noted measles needs a 95 percent vaccination rate for herd immunity.
“The problem is if vaccination rates for these preventable diseases dip too far below the estimated thresholds for herd immunity, we’re worried that we could have multiple epidemics or outbreaks occurring as social interaction becomes a little more normal,” she said in the report from UM.
Although parental vaccine hesitancy gets a lot of attention, Newcomer also said she wants to emphasize it’s not the norm: “The vast majority of parents do support vaccines and do choose to vaccinate their kids.”
She said her broader interest as a researcher is understanding why rural areas of the U.S. have had persistently lower childhood and adolescent vaccination coverage compared to suburban and urban areas.
Newcomer also said UM researchers work closely with local health officers and the Department of Public Health and Human Services, so the findings will reach providers. DPHHS did not return a call for comment by press time.