Survey: 1 in 5 Americans think doctors know vaccines cause autism

It is now four years since Andrew Wakefield was struck off the U.K. medical register and The Lancet retracted his paper that linked the measles, mumps and rubella (MMR) vaccine to autism, but the conspiracy theory he sparked has proven remarkably resilient. The latest survey data suggests 1 in 5 Americans believe doctors know vaccines cause autism.

Data from the survey--which polled 1,351 Americans about some common conspiracy theories--was published in JAMA Internal Medicine. The pollsters asked people whether they agreed with the following statement: Doctors and the government still want to vaccinate children even though they know these vaccines cause autism and other psychological disorders. One-fifth of respondents said they agree with the statement, with a further 36% saying they don't know either way.

The majority of respondents disagreed with the statement, but the large number of people who agree or are unsure shows the difficulty in communicating the science. Within 18 months of the Wakefield paper, epidemiological studies had raised major doubts about his findings--and later investigations showed his research was at best flawed--yet the link still appears valid to a significant minority of people. As reported earlier this month, pro-vaccine messages can actually entrench these opinions.

A 2013 Public Policy Polling survey generated very similar figures to the JAMA data, yet both are slightly at odds with uptake of childhood vaccines. Centers for Disease Control and Prevention figures show that about 90% of kids receive MMR, polio, hepatitis B and varicella shots, suggesting that either one of the data sets is inaccurate, or some parents vaccinate despite believing in the autism link.

- here's the JAMA paper (sub. req.)
- read Regulatory Focus' coverage