This infographic presents some of what we know about immune activation events causing autism and states the vaccine-autism hypothesis.
Given the close association between the immune system activations and autism, supported by animal testing, the vaccine-autism hypothesis is highly plausible.
After all, the purpose of vaccines is to activate the immune system, which is something we know can trigger autism.
Sources are listed and linked below, and I have copied a line from the abstract of each study for the convenience of the reader.
- Hallmeyer, 2015: Autism heritability was estimated to be 38% and the shared environmental component to be 58% https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4440679/
- Atladottir, 2010: admission to hospital due to maternal viral infection in the first trimester and maternal bacterial infection in the second trimester were found to be associated with diagnosis of ASDs in the offspring https://www.ncbi.nlm.nih.gov/pubmed/20414802
- Zerbo, 2015: women with infections diagnosed during a hospital admission, particularly bacterial infections, were at increased risk of delivering a child with ASD https://europepmc.org/articles/pmc4108569
- Vargas, 2005: The brains of people with ASD show a marked activation of microglia and astroglia, and cytokine profiling indicated that MCP-1 and TGF- β1, derived from neuroglia, were the most prevalent cytokines. Cerebrospinal fluid showed a unique proinflammatory profile of cytokines, including a marked increase in MCP-1. https://www.ncbi.nlm.nih.gov/pubmed/15546155
- Li, 2015: Neonatal vaccination of rats with bacillus Calmette-Guérin and hepatitis B vaccines modulates hippocampal synaptic plasticity https://www.ncbi.nlm.nih.gov/pubmed/26531688
- Wei, 2011: The cerebellum of the brains of people with ASD has increased IL-6, which alters neural cell adhesion, migration and synaptic formation https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3114764/
- Abdallah, 2013: The amniotic fluid of mothers of children with ASD showed elevated levels of inflammatory cytokines https://www.ncbi.nlm.nih.gov/pubmed/22175527
- Suzuki, 2013: In multiple brain regions in people with ASD there is excessive microglial activation https://www.ncbi.nlm.nih.gov/pubmed/23404112
- Jones, 2017: The serum of mothers of children with ASD with ID showed increased levels of maternal cytokines and chemokines during gestation https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5122473/
- Tsilioni, 2019: The brains of children with ASD have increase inflammatory cytokines https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6027314/
- Smith, 2007: Maternal immune activation (MIA) in mice alters fetal brain development through interleukin-6 https://www.ncbi.nlm.nih.gov/pubmed/17913903
- Malkova, 2012: MIA in mice results in offspring that show more autism-like behaviours https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3322300/
- Bauman, 2014: MIA in rhesus monkeys yields offspring with abnormal repetitive behaviors, communication, and social interactions. https://www.ncbi.nlm.nih.gov/pubmed/24011823
- Choi, 2016: Either MIA or direct administration to the fetal brain of mice of inflammatory cytokine IL-17a promotes abnormal cortical development and ASD-like behaviors in offspring https://www.ncbi.nlm.nih.gov/pubmed/26822608
- Missig, 2018: Early-life immune activation in mice can lead to long-lasting physiologic perturbations that resemble medical comorbidities often seen in ASD and other neuropsychiatric conditions https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5770773/