Niente autismo dai vaccini

Arthur Caplan ha scritto un articolo sulla leggenda metropolitana che pretende di individuare nel mercurio contenuto in alcuni vaccini la causa della crescita dei casi di autismo negli ultimi vent’anni («Fact: No link of vaccine, autism», Philadelphia Inquirer, 6 febbraio 2007). Si tratta di una sciocca fantasia confutata da tempo, ma che ancora oggi continua a causare tragedie:

What must it be like to spend a huge amount of time every waking day trying to change public health practice – only to find out that you were wrong?
That is precisely what has happened to the proponents of the theory that mercury in vaccines – contained in the preservative thimerosal, which once was used (and is used no longer) in vaccines – is responsible for a nearly 20-year explosion in autism and other neurological disorders among American children.
This urban legend has had very real – and terrible – consequences. It has led, and continues to lead, many parents to avoid getting their kids and themselves vaccinated against life-threatening diseases. The failure to vaccinate has caused many preventable deaths and avoidable hospitalizations from measles, whooping cough, diphtheria, flu, hepatitis and meningitis. And fear of vaccines puts each one of us at risk that we, our children or grandchildren will become part of a deadly outbreak triggered by someone whose parents avoided getting their child vaccinated for fear of autism.
Recent research on many fronts in medicine and science has nailed the coffin shut on the mercury-in-vaccines-causes-autism hypothesis. The connection is just not there. Perhaps the key fact, which has garnered little attention, is that thimerosal has been removed from vaccines in this and other countries for many years, with no obvious impact on the incidence of autism. The most recent data point toward a correlation with nothing at all to do with vaccines: the increasing age at which people (particularly men) have children seems to be associated with an increase in autism and other neurological problems.
Still, some of the most fervent anti-vaccine critics cannot let go. They continue to tell devastated parents of children with autism that vaccines are to blame. Others are still out on the lecture circuit peddling books and articles that bash vaccines and invoke mercury as a problem. Still others pepper the Internet with the false message that vaccines and autism do go hand in hand – it is just that the government, or the pharmaceutical companies, or organized medicine, or all of them, are keeping the truth from us all.

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