“Vaccines cause autism.”
Strong confidence. Large independent cohort studies and systematic reviews across countries consistently find no increased autism risk after MMR or the vaccine exposures studied, including analyses of susceptible subgroups and timing after vaccination.
High-quality evidence does not show that vaccines cause autism. The MMR vaccine, thimerosal exposure and routine vaccination measures studied have not been associated with increased autism risk.
Autism is a neurodevelopmental condition with strong genetic and prenatal contributions. Diagnosis often becomes apparent around the same age that children receive several vaccines, but timing alone does not establish cause.
Safety note: Vaccines can cause expected short-term reactions and rare serious adverse events that differ by product. MMR can rarely trigger febrile seizures, but the evidence does not support autism as an adverse effect.
Talk to a healthcare professional if: Ask before vaccination if there was a severe allergic reaction to a prior dose or component, or if the person is pregnant, significantly immunocompromised or has a condition relevant to a live vaccine.
Evaluate each vaccine by its demonstrated disease-prevention benefits and its documented adverse effects, not by the disproven autism claim.
Use the specific vaccine information statement and discuss real contraindications or prior reactions with a qualified clinician.