Are babies getting too many vaccines too soon?
Here is what the checked sources say. Each title links to the original.
Too Many Vaccines? What You Should Know
CHOP's Winter 2018 Q&A says children may get up to 27 shots by age 2, and up to five at one visit. Those vaccines protect against 14 diseases using about 150 immune-triggering components, versus over 3,000 in vaccines for 8 diseases in the late 1980s, because modern vaccines are more purified. Immunologists Cohn and Langman calculated, theoretically, that babies could respond to about 100,000 vaccines at once. For safety, CHOP points to FDA-required studies testing each new vaccine given alongside existing ones.
Increasing exposure to antibody-stimulating proteins and polysaccharides in vaccines is not associated with risk of autism
A case-control study of 256 children with autism and 752 matched children without it, in three US health plans, with diagnoses confirmed in person. It asked one question: is total vaccine antigen exposure (summed antigen content, not number of shots) in the first two years linked to autism? More antigens, measured to 3 months, 7 months or 2 years, was not linked to autism risk (adjusted odds ratio 0.999 per 25-unit increase). The same held for autistic disorder and autism with regression.
Association Between Estimated Cumulative Vaccine Antigen Exposure Through the First 23 Months of Life and Non-Vaccine-Targeted Infections From 24 Through 47 Months of Age
Some parents worry many vaccines weaken a child's immune system; this study tested one version of that. In six US health systems, 193 children aged 2 to 4 with emergency or hospital visits for infections vaccines don't target were compared with 751 matched children. Estimated total vaccine antigens before age 2 (summed antigen content, not shot count) were nearly identical (240.6 vs 242.9), and more antigens were not linked to these infections (matched odds ratio 0.94, 95% CI 0.84 to 1.07). CDC funded the study; one author disclosed Merck grants.