Abstract
Introduction: Early childhood vaccination rates are lower in rural areas than those in urban areas of the U.S. This study's objective is to quantify vaccine timeliness and the prevalence of undervaccination patterns in Montana and to measure the associations between timeliness and series completion by age 24 months. Methods: Using records from January 2015 to November 2019 in Montana's centralized immunization information system, days undervaccinated were calculated for the combined 7-vaccine series. Undervaccination patterns indicative of certain barriers to vaccination, including parental vaccine hesitancy, were identified. Using multivariable log-linked binomial regression, the association between timing of vaccine delay and not completing the combined 7-vaccine series by age 24 months was assessed. Analyses were conducted in March 2020–August 2020. Results: Among 31,422 children, 38.0% received all vaccine doses on time; 24.3% received all doses, but some were received late; and 37.7% had not completed the combined 7-vaccine series. Approximately 18.7% had an undervaccination pattern suggestive of parental vaccine hesitancy, and 19.7% started all series but were missing doses needed for multidose series completion. Although falling behind on vaccinations at any age was associated with failing to complete the combined 7-vaccine series, being late at age 12–15 months had the strongest association (adjusted prevalence ratio=3.73, 95% CI=3.56, 3.91) compared with being on time at age 12–15 months. Conclusions: Fewer than 2 in 5 Montana children were fully vaccinated on time for the combined 7-vaccine series. To increase vaccination rates, initiatives to increase vaccine confidence and remind parents to complete vaccine series are needed.
| Original language | English |
|---|---|
| Pages (from-to) | e21-e29 |
| Journal | American Journal of Preventive Medicine |
| Volume | 61 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jul 2021 |
Funding
This research was supported by a Center for Biomedical Research Excellence award (1P20GM130418) from the National Institute of General Medical Sciences of the NIH. The authors thank Jon Graham, PhD, and Juthika Thaker, MHA, for their assistance with data management for this study. The study sponsor did not have any role in the study design; collection, analysis, and interpretation of data; writing the report; or the decision to submit the report for publication. The University of Montana IRB approved this study under the exempt category of review (University of Montana IRB #8-19). This research was supported by a Center for Biomedical Research Excellence award (1P20GM130418) from the National Institute of General Medical Sciences of the NIH. SRN led the conception and design of the study, the data analysis and interpretation, and the writing of the article. RF made substantial contributions to the data acquisition, data analysis and interpretation, and writing of the article. BW and SA were responsible for the data acquisition and made substantial contributions to revising the article for important intellectual content. MFD made substantial contributions to the conception and design of the study, data analysis and interpretation, and revising of the article for important intellectual content. All authors have read and approved the final version of the submitted manuscript. No financial disclosures were reported by the authors of this paper.
| Funder number |
|---|
| P20GM130418 |
| 1P20GM130418 |
