A quarter of Americans believe MMR shot causes autism, KFF poll finds

America’s growing anti-vaxx crisis has been laid bare in a national poll that shows huge chunks of the country believe in conspiracy theories about safe shots. 

One-quarter of adults said they believe the measles, mumps and rubella (MMR) vaccine causes autism – a widely studied and discredited claim that emerged in the 1990s.

The Kaiser Family Foundation (KFF) poll also found that a third of adults believe that the Covid shots caused thousands of sudden deaths in otherwise healthy people.

The vaccine-skeptical movement across the country intensified after the Covid pandemic, linked to pushback against Covid vaccine mandates and increased misinformation as people spent more time online.

The growing sentiment has seen figures like Robert F Kennedy Junior surge in polls campaigning on an anti-vaxx message despite being a fringe political figure for most of his years.

The KFF poll showed over a quarter of participants also believed the Covid vaccines have been proven to cause infertility – despite no evidence the Covid shot impacts male or female fertility. 

The survey, the Health Misinformation Tracking Poll Pilot, was conducted from May 23 to June 12 and involved 2,007 adults. It looked at incorrect claims to do with Covid and vaccines, reproductive health and firearms. The most widespread misinformation claims were to do with Covid and vaccines.

Some 10 percent of respondents said the claim that Covid vaccines have killed thousands of healthy people was ‘definitely true’ while 23 percent said it was ‘probably true.’

A conspiracy has emerged in the past few years that the Covid vaccines caused a spike in cardiac issues in healthy young people at a population level. 

But data from the Centers for Disease Control and Prevention (CDC) shows cardiac deaths among Americans under the age of 34 are similar to pre-pandemic levels.

Vaccines have been linked to a very small risk of myocarditis in young people, affecting about one in 30,000 under-40s after their second jab.

But cases are normally mild and resolve on their own without the need for any medical intervention. A Covid infection is also more likely to trigger myocarditis than the vaccines, studies show.

In 2020, data from the CDC showed there were 240 deaths from cardiac arrests among youngsters under 34 years old.

They calculated a rate of about 0.16 deaths per 100,000 people in the age group based on this, with confidence intervals — or the range — of 0.14 to 0.18.

In 2021, there were 284 deaths giving a rate of 0.19 per 100,000 with a range of 0.16 to 0.21.

The intervals overlap, which suggests there is no significant difference between 2020 and 2021 and that the variation is down to natural shifts that occur every year.

Some 23 percent of the KFF study participants also said the statement ‘the MMR vaccines have been proven to cause autism in children’ was ‘definitely’ or ‘probably’ true.

Claims that shots can lead to autism have been peddled by anti-vaxxers for almost 25 years, but the link has been repeatedly disproven.

The disgraced British physician Andrew Wakefield made the claim in a now-retracted 1998 Lancet study.

Dr Richard Horton, editor of The Lancet, publicly described the research as ‘fundamentally flawed’ in 2004 – nine years after it was published.

Dr Horton alleged that Andrew Wakefield, the gastroenterologist behind the paper, was paid by a group pursuing lawsuits against vaccine manufacturers.

The prestigious medical journal finally retracted the paper in 2010.

Just three months after his paper was pulled, Wakefield was banned from practicing medicine in Britain by the General Medical Council.

In 2011, the British Medical Journal conducted a damning probe into the findings of Wakefield’s original study.

Its investigation found only two of the 12 children included developed autistic symptoms after being vaccinated – as opposed to the eight Wakefield claimed.

Since then, studies involving millions of children have failed to find a link between the MMR vaccine and the neurodevelopmental disorder.  

But the rise of concern about vaccines during Covid has led to a dip in childhood vaccine uptake.

Measles is so contagious that around 95 percent of the population must be vaccinated to reach herd immunity. But MMR coverage was at just 93 percent nationally among kindergarteners in the US this year.

According to the CDC, a record high of almost 40 million children missed their measles vaccine in 2021.

This was put down to misinformation surrounding Covid vaccines which spooked parents, causing them to reject normal childhood shots, despite immunizations being the most effective way to protect children from measles. 

In December 2022, a measles outbreak in Ohio saw more than 80 children contract the viral infection. Almost all the cases were in unvaccinated children.