A new global review by the World Health Organisation has again confirmed that vaccines do not cause autism.
This is WHO’s latest position, reinforcing decades of scientific evidence and addressing what it describes as one of the world’s most persistent misinformation claims.
The conclusion—released in a Friday statement titled “WHO expert group’s new analysis reaffirms there is no link between vaccines and autism”—comes from the WHO’s Global Advisory Committee on Vaccine Safety a body of international experts established in 1999 to provide independent scientific advice on vaccine safety.
According to the statement, the new analysis “found that, based on available evidence, no causal link exists between vaccines and autism spectrum disorders (ASD).”
It added that the findings “reaffirm WHO’s position that childhood vaccines do not cause autism.”
The Committee, which met on 27 November 2025, reviewed evidence from 31 primary research studies published between January 2010 and August 2025, spanning multiple countries.
These studies examined the relationship between thiomersal-containing vaccines and ASD as well as broader concerns about whether any vaccines are associated with autism.
WHO said the collected data “strongly supports the positive safety profile of vaccines used during childhood and pregnancy, and confirms the absence of a causal link with ASD.”
The Committee also evaluated long-running claims about aluminum adjuvants—small amounts of aluminum salts used to strengthen vaccine effectiveness.
Drawing on studies conducted from 1999 to March 2023, as well as a “recent large cohort study analyzing nationwide registry data of children born in Denmark between 1997 and 2018,” the group found no evidence of any connection.
“In summary,” the statement said, “the available high-quality evidence shows no association between the trace amounts of aluminum used in some vaccines and ASD, supporting the ongoing use of vaccines with aluminum adjuvants.”
GACVS reaffirmed earlier positions issued in 2002, 2004 and 2012, stating again that “vaccines, including those with thiomersal and/or aluminum, do not cause autism.”
Following the review, the WHO urged governments to rely strictly on scientific evidence when making vaccine policies.
It read, “WHO advises all national authorities to rely on the latest science and ensure vaccine policies are grounded in the strongest available evidence.”
It emphasised that vaccines have been one of the biggest drivers of human progress over the past half-century.
According to the organisation, “Global childhood immunization efforts represent one of the greatest achievements in improving lives, livelihoods and the prosperity of societies. During the past 50 years, childhood immunisation has saved at least 154 million lives.”
President Donald Trump insisted in September that pregnant women should “tough it out” and avoid Tylenol due to an unproven link to autism, and also urged major changes to the standard vaccines administered to babies.
Neither the painkiller Tylenol nor vaccines have been shown to cause autism, WHO had countered a day after.
