A study released at the end of April might have been better to release on the first day of that month. Then anti-vaccine advocates across the interwebz could have claimed it was an April Fool's joke given that researchers found, once again, that a beloved anti-vaccine claim is, in fact, bunk. How do vaccines cause autism again? Oh yea, as this helpful link reminds you, they effing don't.

But no harm in giving that rotting corpse of a horse yet another good hard drop-kick to the rib cage, right? After all, this horse has been known to be one of the hardest zombies to kill this side of Crazyville.

Okay, I'll back up and play nice. There was a time, very, very briefly, when some smart people legitimately worried about the possibility that vaccines could cause autism. The idea stemmed from a now-infamous, and now-retracted, 1998 study linking autism to the measles-mumps-rubella (MMR)vaccine, but that was before we learned what a liar and a fraud the lead doctor was on that paper. (He has since, appropriately, lost his license to practice medicine in England, so he popped across the pond and settled in Austin, Texas, to continue selling his pseudoscience.)

By now, however, dozens of studies have confirmed again and again that there is no link between vaccines and autism. In fact, this most recent study looks at exactly that – a grouping of the studies comparing either kids with and without autism or kids who did and didn't get certain vaccines. When several studies on the same research question have been published, someone at some point often decides to do a meta-analysis of them, analyzing all their data together.

So, some Australians did that with ten studies on vaccines and autism. Five of them, involving over 1.2 million kids, were cohort studies, which means the researchers followed kids to see who did and didn't develop autism spectrum disorders. The other five were case-control studies involving just shy of 10,000 kids. In a case-control study, you find a bunch of kids with autism, match them to kids without autism who share other characteristics with them, and then you look to see who did and didn't get which vaccines.

So when the researchers looked at all these studies' data together, they came to this groundbreaking conclusion:

Vaccines. Don't. Cause. Autism.

Actually, they said the MMR vaccine didn't cause autism because that's what they looked at, but there are still heaps of studies showing that none of the vaccines cause autism spectrum disorders.

But wait — there's more. Anti-vaccine advocates are like pitbulls – once they bite, they don't let go. So when early studies showed no link between the MMR vaccine, they just shifted those goal posts a wee bit and claimed that thimerosal, a preservative made with ethylmercury that once was found in some childhood vaccines (though not the MMR)*, was what caused autism. And the authors of this study looked at that too and found, again, this earth-shattering news:

Thimerosal doesn't cause autism.

Mercury doesn't cause autism.

Of course, I don't really think this study will put the matter to rest for the die-hards. Those who believe in a vaccine-autism connection are the same folks who believe Neil Armstrong did nothing but walk in a movie set. The funny thing about all of this is that if you gave me the option to choose whether I could inject my children with a vaccine that would give them autism or I could leave them unprotected against serious diseases, I would choose autism. People who think differently about the world are more interesting. Certainly more interesting than dead people.

*That sentence has been corrected. I previously stated thimerosal had been found in the MMR, which is incorrect. It was never used in the MMR but was previously used in other childhood vaccines.