Early Childhood Mortality and 2-Month Vaccination

Background: The Louisiana Department of Health matched immunization records to death records for children who died before 36 months of age in 2013–2024. Of about 5,800 such deaths, 1,775 were exactly matched. This analysis uses the 1,225 matched children who died on or after day 90 of life. Methods: Exposure was a recorded dose of a specified vaccine on days 60–90. The comparison group was children with no recorded dose of that vaccine on days 60–90. Children with a first dose of the vaccine before day 60 were excluded from the corresponding single-vaccine contrasts, except for hepatitis B. The outcome was death on days 90–120 versus death after day 120. All children in both outcome groups died before age 3. Odds ratios describe that timing contrast. The comparison group is not a never-vaccinated population: inclusion required a match to an immunization record, and a child had to have been immunized at least once to appear in the study. Results: Among 343 children with no recorded 2-month dose in the window, 52 (15.16%) died on days 90–120. The corresponding shares were higher in every vaccinated group, from 19.17% (polio, 148/772) to 30.65% (Vaxelis, 19/62). For single vaccines, the only contrast for which a confidence interval excluding 1 was rotavirus: odds ratio 1.74 (95% CI 1.26–2.41), p = 0.0005. Odds ratios for the other single vaccines ranged from 1.29 to 1.42. Receipt of all five vaccines first recommended at 2 months (DTaP, rotavirus, Hib, polio, pneumococcal), versus none of those five in the window, had odds ratio 1.60 (1.12–2.32), p = 0.0084. Adding hepatitis B, the six-vaccine contrast was 1.68 (1.16–2.46), p = 0.0043. In sex-stratified contrasts the female odds ratios were larger than the male odds ratios; several female intervals excluded 1, as did the male rotavirus contrast. When considered separately, odds ratios were larger for Black than White children; with intervals greater than 1.0 for Black children in the rotavirus, five-vaccine, and six-vaccine contrasts, with no significant effect in white children. Cause-of-death counts were assessed. Among female deaths on days 90–120, 14 of 19 deaths in the comparison group and 37 deaths in the vaccinated group were coded to ICD-10 chapters R or W. Under a constant-proportion assumption 13 other-cause deaths are expected in the vaccinated group and counted 25. Three vaccinated female deaths were coded to infectious disease and four to nervous-system disease, with zero comparison-group deaths in either category. Conclusion: In this deaths-only, registry-matched study, recorded vaccination on days 60–90 was associated with higher odds that death occurred on days 90–120 rather than later, before age 3. The data do not estimate the probability of death, do not identify a cause, and do not support statements about aluminum dose, antigen load, or vaccine-specific harm. Confirmation would require a cohort with a denominator of living children and adjustment for the reasons vaccination is given or delayed.