You may have heard the worrying suggestion that the MMR vaccine causes autism. Thankfully, this is most certainly not true. So why exactly is it suggested?
In 1998, a paper was published in a scientific journal called The Lancet, authored by Andrew Wakefield, in which he argued that 12 children with autism had developed the condition from the MMR vaccine. This paper was later retracted by the journal as it provided no actual evidence for a link between autism and the vaccine, included falsified data, and Wakefield had failed to declare a massive conflict of interest. Before the study started, the parents of some of the children were trying to sue MMR manufacturers, because they believed the MMR vaccine had caused their children’s autism, and Wakefield was recruited and paid by lawyers to find that link1.
Consequently, Wakefield was struck off the medical register for his deeply unethical actions, although many would suggest that his punishment was not great enough. Wakefield is responsible for initiating the deeply troubling anti-vaccination movement, which is allowing infectious diseases that we were doing quite well to control, to kill more and more people. Even today, he continues to publish books and “whistle-blowing” documentaries which claim to reveal an institutional cover-up of the link between MMR vaccines and autism.
In response to this, the international medical community has invested huge amounts of time and money over the past 19 years, to find out if there really is any increased risk of autism from having the MMR vaccine. As a result, after all of the controversy and fear-mongering, the MMR vaccine is now the one thing which we can be most certain does not cause autism, because so much money has been spent, on study after study, looking for this alleged link2. But this has all come at a cost – fewer studies researching the true, still mostly unknown, causes of autism.
The scientific method
In science we can never say anything with absolute, 100% certainty, because as the weight of evidence grows larger and larger, we simply make it less and less likely that an alternative is true. But when all of the evidence points overwhelmingly in one direction, we allow ourselves to think of things as facts. Evolution is a fact. Climate change is a fact. “The MMR vaccine does not cause autism” is a fact.
The reason so many people put their trust in science, is that they know that one or two studies, or even half a dozen, could get things wrong for one reason or another, but eventually, with lots of different ways of looking at a problem, we will find the right answer. Nothing is ever taken for granted, everything builds upon previous work, and nothing is left unchallenged. The reason scientists feel comfortable accepting that evolution is true, is because every possible attempt to disprove it has been unsuccessful. And the UK’s National Autistic Society is clear “that there is no link between autism and the MMR vaccine”, because unbelievably, unnecessarily large amounts of time and money have been spent looking for this link, and found none3.
So what are the dangers?
Vaccines are effective because of herd immunity. If 95% of a population (for example) are vaccinated, a disease can be all but eliminated as there are not enough hosts for it to jump between. So the 5% who do not get vaccinated are also reasonably well protected from the disease. However, if more and more people forego vaccination, then there are suddenly enough hosts for the disease to spread between, and new outbreaks can occur. In 1996, 92% of people in the UK were MMR vaccinated, and there were just 56 reported cases of measles. 12 years later, the number of cases hit 1,348, after the number of people vaccinated had dropped to around 80%4. Wakefield’s falsified paper was quite clearly to blame, although equally responsible were the media, with their scaremongering and inaccurate reporting of this story. Media coverage was typically very poor – many outlets reported on Wakefield’s tiny anecdotal study whilst ignoring the enormous weight of quality evidence pointing to the safety of MMR.
Vaccines have enabled us to fight back and even wipe out infectious diseases which were killing people in their millions. Smallpox was the first human disease to be eradicated globally in 1980, and it was responsible for killing 2 million people as recently as the year 19675. Subsequently, vaccines have allowed us to eradicate a second disease, Rinderpest, which was a mass killer of livestock. Without vaccines, each of us, and each of our children, would be susceptible to horrendous, life-threatening diseases. And that is the very real danger that this anti-vaccination movement is amplifying. Just look at news reports from the past few years and you can see evidence of measles outbreaks in parts of the world that we thought had brought it under control – London in 2016, California in 2015 and Swansea in 2013. In the developing world, huge numbers of people are still dying from infectious diseases every day, and it is vital that we provide vaccines to protect people from these diseases.
So why does anyone believe it?
People like conspiracies. They like believing that mainstream science has got something completely wrong, and that government is secretly harming or controlling its people. It would not surprise me if many of the people who are anti-vaccination are also climate change deniers, or even evolution deniers. But there is no doubt that many bright, well-meaning people out there have simply got the wrong end of the stick, and that desperately needs to change.
After a turbulent 2016, it seems we are now living in the post-truth era, where made up, non-sensical, “alternative facts” can be given as much time as legitimate truths. They might sound harmless, but when decision makers use “alternative facts” as justifications for their actions it is simply a tactical way of deceiving the public, and outright ignoring the established evidence. This is an incredibly dangerous situation, and can only be avoided by ensuring that the voices of our respected experts are being heard, particularly when bad science or made up shit hits the headlines. Experts owe it to us to stand up and speak out, and we would be wise to listen carefully.
Picture credit: Amanda Mills, USCDCP
- Brian Deer – “Revealed: MMR Research Scandal” Reprint of The Sunday Times
- University of Oxford – Vaccine Knowledge Project
- The National Autistic Society: Our position – MMR vaccine
- BBC News – Q&A: Measles 28th November 2008
- World Health Organisation – Smallpox