Anti-vaxxers of various affiliations have been popping up around Facebook lately, for a number of reasons. In Brazil anti-HPV vaccination is starting its roll-out. At the same time, outbreaks of diseases that were practically eradicated in the US are being detected in many places, such as a recent spate of cases in NY.
As usual, lots of people (sometimes but not often including me) try to argue people out of this dangerous stupidity.
But reasoning doesn’t seem to be enough for the antivaxx crowd, for a number of reasons. For one thing, there is intellectual dishonesty. During an only discussion about vaccine safety, I was pointed to an YouTube video with a (deceptive, as we will see) title that suggested that a strange illness affecting children from a certain African region was due to vaccines. Well, I watched the video, and guess what: there was not A SINGLE WORD in it about vaccines. The experts repeatedly stated that they do not know what causes it, and the only commonality between the affected children cited was that they all had onchocerciasis. Having my curiosity piqued, I did a quick search on Google Scholar for papers about that illness. It’s not even a recent problem, I found references from 1979, and all the articles I looked at reiterated the unknown etiology.
Coincidentally, a few days earlier Mother Jones reported a study that indicated that people who are in denial about certain issues – such as vaccines, for instance – develop a paradoxic reaction to being exposed to facts that contradict their beliefs – they dig in even further in the lunacy. Soon afterwards, another article supplemented this one with further examples of people being locked in a mindset in such a way that even when presented with plain facts they dig further in – in fact, being shown that they are factually wrong makes it even worse.
I stumbled on this problem recently discussing with an alt med practitioner about the link between HPV and cervical cancer, and despite the fact that I could easily point out to a mountain of published evidence, from studies that used a wide variety of methods, from molecular biology to epidemiology, and even to a publication by the IARC, a WHO institute that is the main centre for cancer research in the world, that person wouldn’t be swayed by this, dismissing everything with a wave of hand because all that evidence doesn’t fit the preconceived (and rather unscientific, I should add) notions of that particular brand of lunacy, er, alt practice.
A common argument of denialists is that medicines (like vaccines) are produced by industries which are interested only in their bottom line. Well, I’m sorry to inform that I got there first. Yes, this is true. Nevertheless, there are evidences produced by public health researchers that show that many of those do work as claimed. The pharma industry is indeed not to be blindly trusted, but even its shenanigans eventually come to light. The cases when medicines did not quite work or had terrible side effects (e.g. the Vioxx case) were detected by the medical community, despite the crippling plague of the euphemistically called “conflicts of interest”.
There is a massive global system of vigilance for side effects of vaccines, the necessary scale of a conspiracy to hide relevant side effects of vaccines that for the most part have been in use for decades is simply unfeasible.
I invoke Occam: what is the simpler explanation, that such side effects are rare and limited, or that there is a worldwide conspiracy to hide them, involving not only the industry but every public health officials and experts in the world, including (humbly) yours truly?
Yes, there are risks with vaccines, especially those made with live viruses, but the risks of not vaccinating are far superior. And I’d like to remind people about something I thought was a widely known fact, but realized wasn’t the case. Small children who are not old yet to be vaccinated are protected by what we call “herd immunity”. That also protects people who can’t be vaccinated because of compromised immunity. If the proportion of vaccinated people falls below a certain threshold, usually around 80% or more, those persons are at risk. And since their immune system is relatively fragile, infectious diseases in them are usually more severe, sometimes even fatal. So vaccination is a public health issue and in my opinion should be mandatory, period.
For more information, I’d recommend a concise but rich blog post on this subject from a mother who is also a scientist.