Scientific References on Vaccine Safety and Efficacy
Studies assessing potential links between Vaccines and autism
A cohort study of Danish 467,450 found no relationship between thimerosal-containing vaccines and risk of developing autism. Journal of the American Medical Association: https://jamanetwork.com/journals/jama/fullarticle/197365
A nationwide cohort study of 657,461 Danish children found no increased risk of autism among children who were vaccinated, including among those with risk factors like a diagnosed sibling. Annals of Internal Medicine: https://www.acpjournals.org/doi/10.7326/M18-2101.
A retrospective cohort study of 537,303 children found NO difference in risk of autism between vaccinated children and unvaccinated children. There was also no association between age at the time of vaccination, time since vaccination, or date of vaccination and development of autism. New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/nejmoa021134.
A retrospective cohort study of over 500,000 US children with ASD found no increased risk of adverse events or exacerbation of autism-related symptoms following vaccination, including fever or emergency room visits. Vaccine: https://pubmed.ncbi.nlm.nih.gov/35315325/.
A retrospective cohort study of 95,727 US children who received the MMR vaccine with older siblings with and without autism found no link between MMR vaccination and risk of autism, even for children with a sibling with autism. JAMA: https://jamanetwork.com/journals/jama/fullarticle/2275444.
An epidemiological analysis of children found prevalence of autism was the same between vaccinated and unvaccinated populations. Age of diagnosis did not differ, and onset of symptoms of autism were not linked to when they received MMR vaccination. Lancet: https://pubmed.ncbi.nlm.nih.gov/10376617/.
A global review by the Institute of Medicine (US) Immunization Safety Review Committee found NO relationship between vaccination status, autism diagnosis, autism rates before and after introduction of the MMR vaccine, and no plausible mechanisms in which thimerosal or vaccines could cause autism. This used data from hundreds of thousands of children, millions of vaccine doses, across the United States, Denmark, Sweden, and the United Kingdom. The National Academies: https://pubmed.ncbi.nlm.nih.gov/20669467/.
A systematic review of 67 studies involving millions of children assessing the safety of the overall US immunization schedule found that vaccines are safe, adverse events are rare, and routine vaccines like MMR, DTaP, Varicella, and others have no relationship to developing autism, type 1 diabetes, or other health conditions. Pediatrics: https://pubmed.ncbi.nlm.nih.gov/25086160/.
A scientific review assessed claims about vaccines, autism, and the notion that vaccines overwhelm the immune system concluded there is no evidence to support these claims and they lack biological plausibility based on how the immune system works. Clinical Infectious Diseases: https://doi.org/10.1086/596476.
A systematic review of 10 primary studies assessed potential links between thimerosal, thimerosal-containing vaccines, and ASD found no relationship between vaccines and ASD. Authors emphasized that studies with robust methodologies consistently show vaccines are safe, whereas those claiming to find links to vaccines and autism routinely have substantial biases, conflicts of interest, and methodological flaws. Pediatrics: https://doi.org/10.1542/peds.2004-0434.
Clinical trial data on vaccines
The polio vaccine was tested in a placebo-controlled clinical trial that enrolled over 600,000 children (1954). American Journal of Public Health: https://pmc.ncbi.nlm.nih.gov/articles/PMC1622939/.
Double-blind, placebo-controlled trial of the measles vaccine (1966). Pediatrics: https://doi.org/10.1542/peds.37.4.649.
Double-blind, placebo-controlled trial of the Varicella-Zoster vaccine (1984). New England Journal of Medicine: https://www.nejm.org/doi/abs/10.1056/NEJM198405313102201.
Double-blind placebo-controlled trial of the Pfizer RSV vaccine. New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/NEJMoa2213836.
Double-blind placebo-controlled trial of the GSK RSV vaccine. New England Journal of Medicine: https://www.nejm.org/doi/pdf/10.1056/NEJMoa2209604.
Double-blind placebo-controlled trial of the HPV vaccine (Gardasil 4) in preventing cervical cancer. New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/NEJMoa061741.
Double-blind placebo-controlled trial of the Rotavirus vaccine, including 70,000 participants. New England Journal of Medicine: https://www.nejm.org/doi/10.1056/NEJMoa052664.
Double-blind placebo-controlled trial of the Pfizer COVID-19 vaccine. New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/NEJMoa2034577.
Double-blind placebo-controlled trial of the Moderna COVID-19 vaccine. New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/NEJMoa2035389.
Double-blind placebo-controlled trial of the Novavax COVID-19 vaccine. New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/NEJMoa2107659.