Updated: Nov 9, 2020
Even in 2020, approximately 1 in 6 caregivers of autistics believes vaccines may be the cause of autism. Of beliefs regarding the cause of autism, vaccines (16.5%) is fourth behind beliefs of genetics (58.4%), environmental influences (21.9%), and birth complications (16.9%). Caregivers who endorse the vaccine connection often have children requiring more “substantial levels of support,” and over 50% have children with regressive autism. In regressive autism, a child has seemingly normal development, but then, typically between 1 to 5 years of age, the child’s development stalls or regresses especially in regard to social function and communication. Regressive autism accounts for approximately 30% of all autism. I can see how regression in the development of a child coinciding with the age that vaccines are given would enhance the belief in the vaccine-autism connection. The vaccine debate is ever looming, with particular focus on the measles-mumps-rubella vaccine. Some people argue that no good studies have been done to negate the claim. Yet, one research article worth mentioning is a paper by Madsen et.al., in which all children born in Denmark from 1991 to 1998 were evaluated for diagnosis of autism by MMR vaccine status. This study, including over 500,000 children (>400,000 vaccinated (82%) and >96,000 unvaccinated) showed no difference regarding autism diagnoses between these groups. I mention this article due to its enormous size and to counter the argument that there are no major undertakings to quell this debate. The data demonstrates MMR does not cause autism, and I’d like to think this is the end of the MMR vaccine-autism question, but the incidence of autism in this study is rather small with only 738 diagnoses in total, an incidence of 1-2/10,000 children. Even in the 1990s, this is a conservative estimate. The article states that only specialists in child psychology may make the diagnosis of autism in Denmark, and hence, quote high validity in their diagnoses. In some ways this offers a more uniform diagnosis, and likely results in more clear cases, such as those requiring greater care. This kind of entire nation evaluation should help put an end to the debate, but again, I can see how regression in the development of a child coinciding with the age vaccines are given would cause concern, especially in the age of social media.
1. Fombonne E, Goin-Kochel RP, O'Roak BJ; SPARK Consortium. Beliefs in vaccine as causes of autism among SPARK cohort caregivers. Vaccine. 2020 Feb 11;38(7):1794-1803. doi: 10.1016/j.vaccine.2019.12.026. Epub 2020 Jan 8. PMID: 31924427.
2. Madsen KM, Hviid A, Vestergaard M, Schendel D, Wohlfahrt J, Thorsen P, Olsen J, Melbye M. A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med. 2002 Nov 7;347(19):1477-82. doi: 10.1056/NEJMoa021134. PMID: 12421889.