Study: Early and/or More Childhood Vaccinations Not Beneficial

5 hours ago

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A study by T. Yengst et al titled “Comparative Health Outcomes of Vaccinated versus Unvaccinated Children: A Retrospective Cohort Analysis” published on 26 September 2026 supports the objection that children’s vaccinations are not always helpful.

The paper is 23 pages long, with the main text at about 15 pages. The remaining are references and tables.

This is not the first study about the long(er)-term impact of childhood vaccination. The authors mention a few examples in their introduction. One is reproduced below.

Enriquez et al. (2005), in the Journal of Allergy and Clinical Immunology, provided a pivotal analysis by comparing self-reported atopic disease prevalence across distinct vaccination strata. Their cohort included 515 never-vaccinated children and 239 completely vaccinated children. The results were striking: the authors reported that asthma prevalence was 21.3% in completely vaccinated children compared to only 3.7% in never-vaccinated children (p < 0.0005).

In this study, data was extracted from 8 pediatric primary care practices in the US. Vaccinated status is defined as having received at least one dose before 13 months of age. Unvaccinated status is defined as having zero doses at any point before 13 months of age.

The final sample is 6,239 children, consisting 3,259 male and 2,980 female with a mean age of 7.6 years. The vaccinated group consists of 2,414 (38.7%) and the unvaccinated group 3,825 (61.3%).

Rhinitis is significantly higher amongst vaccinated children with an odds ratio (OR) of 1.8 (95% CI: 1.6–2.1); that is, an 80% increase in odds compared to the unvaccinated. Also, ear infection OR is 2.0 and respiratory disease OR is 1.6. Developmental delay is not significantly associated with an OR of 0.9. Other conditions such as fever and abnormal breathing are approximately equal.

The study included a dose-response analysis with the 1st quartile having received 1–3 vaccines, 2nd quartile 4–5 vaccines, 3rd quartile 6–9 vaccines and 4th quartile 10+ vaccines. For ear infections, the OR is more or less constant. For rhinitis, however, the OR rises from 1.3 in the 1st quartile to 2.3 in the 4th quartile.

Developmental delay revealed a complex, non-linear pattern of critical importance. In the 1st Quartile, the OR was 0.82 (p = 0.091)—non-significant but trending in the protective direction. In the 2nd Quartile (OR 0.66, p = 0.012) and 3rd Quartile (OR 0.74, p = 0.016), vaccination appeared significantly protective against developmental delay. However, in the 4th Quartile (10+ vaccines), the association reversed dramatically: OR 1.4 (p = 0.0031), indicating significantly elevated odds of developmental delay among the most heavily vaccinated children.

The study has its limitations. Whilst the sample is not small and taken from 8 practices, any diagnoses and vaccinations outside may not have been recorded. Also, each hosehold’s habits are different—vaccination is merely one factor—so there can be bias either way.

Nevertheless, the results corroborate previous studies, and with some conditions having an OR of ~2.0 or higher, it shows that early and/or a higher number of vaccinations for children are not beneficial. To quote the authors: “These are not subtle effects.”