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Current time:0:00Total duration:9:51

Vaccines and the autism myth - part 1

Video transcript

so for the last 20-30 years we've noticed this increase in autism I'm actually going to quickly sketch out a graph to show you what I mean we have autism rates over here and if you follow them over time basically what happens that you see that things are going upwards and the main reason that people cite is awareness they say well if more parents and families are aware of autism because you know we talk about it more nowadays then of course they're going to bring it up with their doctors and it's going to get diagnosed and although that may be one reason for the increase people have been searching for other reasons to explain the increase as well now in 1998 there was a team of doctors and researchers that put together a study a study that we call the Wakefield study it's named after the main author which was a guy named dr. Wakefield he was a surgeon working in England and in total there were 13 people 13 authors on this study so this study was done in the United Kingdom the UK and what they did is they took 12 children and these children came into the hospital reportedly kind of the normal way the routine way that children come to the hospital they weren't recruited and he found that they had developmental problems so these are 12 children with some sort of developmental problem or delay and the most common example of a you know developmental problem among these kids was autism so a lot of these kids ended up having a diagnosis of autism and what they did I'm actually going to sketch out for you so let's imagine that this is the head of one of our children what he asked them was you know do they have any symptoms when do their symptoms start all these kinds of things to kind of get it their history their medical history and a lot of the family said well you know we remember them having the symptoms of autism which I'm drawing is kind of a grayed out brained and there seems to be this is the parents talking up they felt like there's some sort of relationship with the vaccine they felt like they remembered the vaccine specifically the MMR vaccine the measles mumps rubella vaccine around the time that symptoms began and that's what he reported so we actually have now a relationship based in terms of parents recollection between the vaccine and autism but what this study was mainly about was actually the gut so he was a surgeon and he wanted to look at the intestines of these kids and he noticed that on the intestinal biopsies when you actually got a little bit of tissue from these intestines a lot of them had inflammation that was what his paper was primarily about was this inflammation that he saw so he proposed and this is a big deal he proposed that vaccine was causing this inflammation he thought that was the cause of the inflammation and he then thought that perhaps there was some mystery protein let's say this blue little protein that maybe you take in through your diet that can now because it's inflamed can get across the gut and can affect the developing brain so this was how he proposed there could be a link between the vaccine and autism now when the Wakefield study first came out in 1998 you can imagine the kind of excitement that's created for a lot of parents and families that have been for years looking for something to explain why their kid had autism and so finally people could kind of circle this and say ah maybe it was the vaccine that caused autism that's what people thought but there were a couple of problems with this idea the first problem was that some of the patients that had autism symptoms they actually reported that they were having these symptoms before they had any of the gut symptoms now think about that if you're having autism symptoms before gut symptoms not after then that really goes against this theory because this theory is based around the idea that it's the gut that comes first so immediately this is one concern and kind of a big question mark over here whether this is really true another question mark is around this mystery protein I'll put it up here so this mystery protein this is something that Wakefield never really identified he never said well I think it's this protein or that one and in the last 15 plus years nobody's found any mystery proteins that would explain what Wakefield was suggesting so the fact that nobody can actually find these proteins is also another big question mark nevertheless a lot of studies started getting done you know people started saying well if there truly is a relationship between vaccines and autism then let's explore that further so a group of studies were done around MMR vaccine rates how often in a population do you actually see people getting the MMR vaccine and you'd imagine that if there truly is a link between vaccine causing autism if that's true then of course the vaccine rates must be going up you know that would explain the autism going up and so they actually looked in a few different places and of course the first place to talk about is the UK because of course this study was initially done in the UK and in the UK they looked over six years and they found that actually MMR vaccine rates had been steady there had not been an increase so already this is a little weird if we're thinking that the vaccine is causing autism you would expect something different so they looked again they actually looked another time this time they actually looked in the US and in the United States they did this study over 15 years and over 15 years same thing steady vaccine rates even though autism rates were going up now another study was actually done this time in Canada and surprisingly in Canada turns out that the vaccine rates are actually going down slightly so vaccine rates over 12 years now went down even though autism rates were going up so this data is done at the population level but it really does go against this idea that vaccine is causing autism but people weren't satisfied with that they wanted more specific research to be done on this mechanism that dr. Wakefield proposed so another study was done and actually was done in the United Kingdom and this study looked at 473 autistic children so remember the initial study was done on 12 children and now we're looking at hundreds of children with autism and among these 473 they actually wanted to figure out this part of they said is there a link between vaccine and any sort of gut inflammation and the answer was a resounding no there doesn't seem to be any relationship in autistic kids with vaccine MMR vaccine and inflammation of the gut so that was actually very detrimental to Wakefield's theory but what about this second part the second link you know between gut inflammation and any sort of autism this part right here well again another study in the UK looking this time at two hundred and sixty two autistic children found that there was no link between these two things so gut inflammation and autism did not seem to be related at all so now the two important components of Wakefield's idea didn't seem to bear out and then I should also just kind of cross this off this mystery protein bit because again people had been looking for that and no one seemed to find that but that wasn't good enough because you could say well maybe there still is some link between vaccine and autism but maybe this mechanism wasn't quite right so research got done on this purple arrow over here so they said okay what about this you know could it be possible that there's a link between the two using some other mechanism and so the study was done in the UK specifically looking at MMR vaccine and autism is there a relationship and it turns out that they in this study looked at 71 autistic children and they found that among these children there was no relationship and this study was actually in a way done again in fact in another setting done in a different way but also trying to answer the same question of a link between vaccine and autism in Finland this time they found that among 309 autistic children there was no link now remember this link that we created was done among 12 children and now we have hundreds and hundreds of kids in different countries another one was done in the US and all these studies are kind of finding the same result that basically there were no links that they could find between vaccine and autism and so people started really doubting the truth behind that very first study that first study done on 12 kids but people were still talking about it and said you know what about that Wakefield study know isn't it possible that there could still be a link in in spite of all this other evidence so finally a group out of Finland tried to do another type of study a different approach that they thought would kind of conclusively answer the and they basically said well fine why don't we follow 1.8 million children so obviously this is many many children that are getting vaccinated and just follow them over time and see if they develop autism and this might kind of answer once and for all whether there's a link and so they followed these kids over time and they found a grand total of zero cases of vaccine associated autism so in all these cases of vaccination none of them resulted in autism so this point people really stopped believing the study the Wakefield study and whether there was any link that was kind of resolved all these studies kind of said no there was really no link between vaccine and autism but a question remained around the Wakefield study and how those results were found in the first place I'm actually gonna pause right there we'll jump into that in the next video