Lately I have seen a great deal of articles claiming the MMR
vaccines cause autism. This is honestly a little frustrating to me as such
claims are simply lies. To fully deal this this issue I am going to quickly explain
some basics about our immune system and then what exactly the MMR vaccine is.
Our immune system has two main parts, the innate and the
adaptive immune system. The innate immune system is only able to detect
pathogens that are very different from the stuff we already have in our body.
Cells like macrophages are constantly looking for anything that is different
from our normal cells and proteins. If they find something like a bacterium
they engulf it and degrade it. Viruses however are very small and they use our
own cells to replicate, this means they are next to impossible for our innate
immune system to detect. This is where our adaptive immune system takes up the
slack. It works in three stages, exposure, protective immunity and memory. The
exposure stage is the first time we are infected with a virus, during this time
our bodies learn what the virus looks like and then begins to prepare for the
next time you see it. In the protection phase our immune system knows what the
virus looks like so it is able to stop it before it makes us sick. The memory
stage is where we have made cells and proteins (called antibodies) that will
remember what the virus looks like for years. This is why you never get sick
from the same cold virus.
Vaccines take advantage of our adaptive immune system, they teach
our immune system what the virus looks like before we get infected. This stops
us from ever getting sick from that pathogen. In the case of the MMR vaccine it
uses live attenuated virus. Live attenuated virus is a form of the pathogen
that has been genetically modified so that it can no longer cause disease but
it is still enough like the bad form that it can prepare our bodies for the
real thing. The MMR vaccine prevents infections of measles, mumps, and rubella;
all three of these diseases are caused by viruses.
Before I talk about MMR vaccination and autism I would like to
reiterate something I have said in the past. When you are reading something
think about where the information is coming from, is it a credible site, do
they include references to scientific articles. If you are uneasy about where
the information is coming from I would suggest going to more credible sources. There
a ton of anti-vaccination sites that claim the MMR vaccine causes autism
however they never site credible scientific research.
Andrew Wakefield was the original author of the study
published in the Lancet that claimed there was a link between MMR vaccinations
and autism. That article has been retracted as its results discounted by the
medical community. At the time Mr. Wakefield was conducting this research he
was paid 400,000 euros from a law firm that was preparing to sue MMR vaccine
producers. Before publishing any scientific paper you are supposed to document
any conflict of interest that you may have. If Mr. Wakefield had mentioned this
before submitting his paper it would have never been published.
Mr. Wakefield has been banned from practicing medicine in
the UK and is not licensed to practice in the US1.
In retracting the article this is what the Lancet had to
say:
“Following the judgment of the UK General Medical Council’s
Fitness to Practise Panel on Jan 28, 2010, it has become clear that several
elements of the 1998 paper by Wakefield et al are incorrect, contrary to the findings
of an earlier investigation. In
particular, the claims in the original paper that children were “consecutively
referred” and that investigations were “approved” by the local ethics committee
have been proven to be false. Therefore we fully retract this paper from the
published record”2
Further studies have looked to see if there is any link. All
credible research has shown that there is absolutely no causal link between MMR
vaccinations and autism3,4,5. They do not cause autism.
If anyone claims that MMR vaccinations cause autism they are
lying or severely misinformed.
References
