Maternal Immune Activation and Autism

The diagram in the infographic above comes from:

The Vaccine-Autism Hypothesis

Here are the sources for each point in the above infographic.

Genetic / Environmental Etiology

The Claim: Autism is partly but not wholly genetic; it can be triggered in genetically susceptible individuals by environmental factors that alter neurodevelopment

The Sources:

Infections in Pregnancy

The Claim: A wide range of bacterial and viral infections during pregnancy are associated with autism, so one trigger is a serious immune activation event during a critical stage of neurodevelopment

The Sources:

  • 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
  • Zerbo, 2015: women with infections diagnosed during a hospital admission, particularly bacterial infections, were at increased risk of delivering a child with ASD

Immune Activations in Animals

The Claim: Immune activations in pregnant or newborn animals alter neurodevelopment and increase autistic-like behaviors in the pups and infants; multiple immune challenges multiply the effect.

The Sources:

Inflammation and Autism

The Claim: Inflammation is an immune system response to a challenge.  Inflammation is associated with autism.

The Sources:

Vaccines and Immune Activation

The Quote: “Immune activation is the objective of vaccines”

… is from Matheson vs. Schmitt, Plotkin Deposition, 16:27:56, 11 Jan 2018 or

Here is the context of the quote:

  • QUESTION: Are you familiar with the study called “Maternal Immune Activation Alters Fetal Brain Development through Interleukin-6” [Smith, 2007]?
  • PLOTKIN: Vaguely, yes. Yeah.
  • QUESTION: Published in the Journal of Neuroscience?
  • PLOTKIN: Yeah, well, I don’t remember the journal.
  • QUESTION: Is that one of the journals you consider respectable?
  • PLOTKIN: Yes.
  • QUESTION: And this was out of the University of California Medical Center. This is from California Institute, CalTech. That institution did a number of studies regarding — that group did a number of studies relating to immune activation and neurological disorder, correct?
  • PLOTKIN: Yes.
  • QUESTION: And they found a connection between immune activation and neurological historical disorders, correct?
  • PLOTKIN: Yes.
  • QUESTION: Okay. And one of the study’s findings they had was that immune activation alters fetal brain development through interleukin-6, correct?
  • PLOTKIN: As I said before, IL-6 is an important cytokine. I would point out in relation to immune activation, that immune activation occurs as a result of disease and exposure to a variety of stimuli, not just vaccines.
  • QUESTION: But it can be caused by vaccines, correct?
  • PLOTKIN: Immune activation is the objective of vaccines.

The Claim: Challenges to the immune system can come from wild pathogens or from vaccines

This is confirmed by the quote above from Plotkin, as well as any immunology textbook.

The Claim: Vaccines must activate the immune system strongly in order to work

The Claim: Aluminum adjuvants are used in many vaccines specifically to increase the challenge to the immune system and boost the response

These two claims are basic to how vaccines work, as explained on the websites of the CDC and the CHOP:

 “An adjuvant is an ingredient used in some vaccines that helps create a stronger immune response in people receiving the vaccine. In other words, adjuvants help vaccines work better. Some vaccines that are made from weakened or killed germs contain naturally occurring adjuvants and help the body produce a strong protective immune response. However, most vaccines developed today include just small components of germs, such as their proteins, rather than the entire virus or bacteria. Adjuvants help the body to produce an immune response strong enough to protect the person from the disease he or she is being vaccinated against. Adjuvanted vaccines can cause more local reactions (such as redness, swelling, and pain at the injection site) and more systemic reactions (such as fever, chills and body aches) than non-adjuvanted vaccines.”


 “Aluminum is used in vaccines as an adjuvant. An adjuvant is a vaccine component that boosts the immune response to the vaccine. Adjuvants allow for lesser quantities of the vaccine and fewer doses. The adjuvant effects of aluminum were discovered in 1926. Aluminum adjuvants are used in vaccines such as hepatitis A, hepatitis B, diphtheria-tetanus-containing vaccines, Haemophilus influenzae type b, and pneumococcal vaccines, but they are not used in the live, viral vaccines, such as measles, mumps, rubella, varicella and rotavirus.”