Published July 17, 2026 | Version v1
Journal article Open

Health Correlates of Vaccination: Lessons from Florida's Medicaid Data

Authors/Creators

  • 1. Independent Researcher

Description

Background: Comprehensive evaluation of the risks and benefits of childhood vaccination remains limited by restricted access to large, linked health datasets.

Methods: We analyzed a Florida Medicaid database (1990-2010) containing complete health records for 14,235 children followed from birth through age 10 (156,585 patient-years). Correlations between 14 vaccination categories and 9 diagnostic categories were computed and adjusted for differential diagnosis bias by stratifying patient-years according to the number of well-child visits (ICD-9 code V20) recorded in each year.

Results: Vaccines associated with the least detrimental outcomes were DTP-Hib, HPV, and pneumococcal vaccine; those associated with the most detrimental outcomes were influenza, MMR, and diphtheria-tetanus combinations. The influenza vaccine showed the highest overall correlation with adverse outcomes (R=0.172 with total diagnoses) and was associated with a 4-fold increase in asthma risk and a 3-fold increase in autism risk. Fully vaccinated children were more than twice as likely (47% vs. 21% per year) to be diagnosed with respiratory infections as unvaccinated children; Hib and diphtheria-tetanus combinations were similarly associated with increased respiratory infection risk. Total vaccine burden was associated with more than a 2-fold increase in risk of ADHD, autism, and asthma, and was positively correlated with 8 of 9 tracked diagnoses.

Conclusions: These findings suggest measurable associations, both protective and adverse, between childhood vaccination and downstream health outcomes in this Medicaid population, warranting larger-scale, prospective evaluation of the cumulative vaccine schedule.

Keywords: vaccination; Medicaid; pediatric health outcomes; autism spectrum disorder; asthma; immunization safety

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