A recent evaluation by a global panel of vaccine safety experts, working under the World Health Organization (WHO), has determined that there is no scientific evidence linking vaccines to autism spectrum disorders (ASD). This finding reinforces WHO’s longstanding confirmation that childhood vaccination does not lead to autism.

Formed in 1999, the Global Advisory Committee on Vaccine Safety (GACVS) consists of international specialists who offer independent, science-based guidance to WHO on matters concerning vaccine safety worldwide.

During its meeting on 27 November 2025, the Committee focused its review on potential connections between ASD and vaccines containing thiomersal, as well as vaccines overall. Analyzing 31 research studies published between January 2010 and August 2025, involving data from various countries, the committee found consistent evidence indicating that vaccines given during pregnancy and throughout childhood have strong safety records and show no causal link to ASD.

The experts also evaluated whether aluminum-based additives used in some vaccines could pose health risks. This assessment relied on research conducted from 1999 to March 2023. The Committee additionally considered the findings of a large-scale study based on data from children born in Denmark between 1997 and 2018. The comprehensive data revealed no relationship between the small amounts of aluminum used in vaccines and autism, fully supporting their continued safe use.

Based on its comprehensive analysis, the Committee upholds the conclusions from its earlier assessments in 2002, 2004, and 2012, stating definitively that vaccines—including those containing thiomersal or aluminum—do not cause autism.

WHO urges all countries to follow the latest scientific research in forming vaccination strategies and to base public health policies on reliable evidence. Childhood immunization remains one of the most impactful health interventions of the past five decades, credited with saving over 154 million lives globally.