Regardless of all the research concerning the alleged link between the measles-mumps-rubella (MMR) vaccine and childhood autism, many parents around the world still refuse to inoculate their children against these easily preventable diseases.
As the goalposts of the debate are constantly moved from one concern to another, scientists find themselves coming back to the subject time and again.
Even though it should be clear by now that no new data will ever be enough to convince those who have already made up their minds, a new study – published on April 21 in JAMA – examined the claim that vaccination triggers autism only in those children who are already susceptible to it.
“This study has long been awaited in the autism community – a retrospective look at families where the older sibling has ASD and the parent either does or does not vaccinate the younger child,” said Dr. Paul Offit, Director of the Vaccine Education Centre. “The benefit of this study is that the second child is at higher risk for autism, which makes for a more powerful study.”
To see whether there’s any link between the dreaded MMR vaccine and the prevalence of autism spectrum disorder (ASD), the researchers studied 95.727 children, all of whom had an older sibling. Those 2% of the participants who had a sibling with ASD were considered at higher risk for developing the disability themselves, as autism has a strong genetic component.
When the researchers compared vaccinated and unvaccinated children, both those who did and did not have an older autistic brother or sister, they found no increased risk for the disability among any of the children.
“The findings were what one would expect,” noted Offit. “Therefore, the choice not to vaccinate the younger child didn’t decrease the risk of ASD. It only increased the risk of contracting measles, mumps or rubella.”
The so-called anti-vaccination “movement” had its beginning in 1998, when a British gastroenterologist Andrew Wakefield published a paper in Lancet showing a link between the vaccine and the prevalence of ASD. Later, the study was found to be fraudulent and was eventually retracted. This caused Wakefield to lose his medical licence in the UK.
Over the following 15 years, scientists have looked into any number of worries new parents raised over the safety of vaccination, and found no adverse effects.
But despite the fact that science on this point is now settled, there is no reason to think that the whole debacle is already on its way out.
“Unfortunately, there will still be parents who have reservations about vaccines, but I don’t blame parents – they are only trying to do the best they can for their children,” said Dr. Mark Schleiss, a pediatric infectious disease physician at the University of Minnesota.
“I am more concerned about the financial forces driving the anti-vaccine agenda. Behind every anti-vaccine web site there’s someone looking to make a buck – by selling chelators, vitamins, creams, salves, natural foods, raw milk, nutritional supplements, secretin, electrostimulation, spinal adjustment, books, tapes and video. Fading Hollywood celebrities seek to revive their careers, and proponents of “alternative vaccine strategies” seek celebrity status and write best-sellers. They are preying on vulnerable, resource-limited families who are desperately seeking answers. It’s unconscionable, and no one’s talking about it.”