Nearly a quarter of Americans believe that childhood vaccines and taking acetaminophen (Tylenol) during pregnancy cause autism, despite no evidence to support those claims, a survey published late last week in JAMA Health Forum notes. The findings suggest that misinformation about autism persists and that better public health messaging is needed to combat it.
“We found that non–evidence-based beliefs about risks for autism were prevalent,” wrote the authors, led by researchers at Massachusetts General Hospital and Harvard. The authors also noted “consistent association with political affiliation—greater Republican affiliation was associated with greater likelihood of endorsing non–evidence-based beliefs about risk.”
Older adults least likely to buy into misleading statements
To understand Americans’ perceptions of autism risk, the scientists asked 30,288 adults to participate in a cross-sectional survey, which also included questions about their demographic background and political affiliation.
Genes account for about 80% of one’s autism risk, and it’s considered a heritable neurodevelopmental condition. But over the years, high-profile people such as US Health and Human Services Secretary Robert F. Kennedy Jr. have incorrectly linked childhood vaccines and acetaminophen to autism.
Most survey respondents (about 67%) correctly knew that genetic factors contribute to autism. Yet, about a quarter of participants (27%) blamed childhood vaccines for autism, and almost as many (23%) claimed taking acetaminophen during pregnancy causes autism.
Adults ages 35 to 44 years were most likely to believe misinformation about autism risks, and those aged 65 and older were the least likely. More Republicans than Democrats also believed autism misinformation. President Donald Trump has linked autism to both acetaminophen and childhood vaccines.
We found that non–evidence-based beliefs about risks for autism were prevalent.
Surprisingly, heavier users of social media were less likely to trust inaccurate information about autism.
“We did not identify a positive association between social media use and belief in non–evidence-based risk factors. Indeed, more frequent use was associated with a lower likelihood of endorsing such beliefs,” the authors said. “One possibility is that social media use parallels information seeking more generally—ie, those with lower levels of use are also those with less access to sources of reliable health information.”
The research highlights the increasing influence of politics on public health.
“Our results suggest the complexity of public health messaging in the post–COVID-19 era,” the authors said. “The large proportion of the population holding beliefs that may adversely impact public health (eg, by preventing vaccination) highlights the magnitude of the problem.”