Study Finds No Link Between MMR Vaccination and Autism in 2.5 Million Children

The relationship between childhood vaccination and autism has been extensively investigated, and new large-scale research provides additional evidence against a causal link between the MMR vaccine and autism.

Researchers analyzed health information involving more than 2.5 million children and found no evidence that children who received the measles, mumps and rubella vaccine had an increased risk of developing autism.

The size of the study is important because very large populations allow researchers to detect potential differences that may be difficult to identify in smaller studies. The findings also matter for public health because vaccine misinformation can contribute to declining immunization rates and renewed outbreaks of preventable diseases.

Measles, in particular, is highly contagious and can cause serious complications including pneumonia, brain inflammation and, rarely, death. Maintaining vaccination coverage therefore remains an important component of childhood disease prevention.