Monday, March 11, 2019

The Anti-Vaxxers: Irrational Or Rational?

Frank Bruni, an opinion writer at the New York Times, has a good take on what he calls the horror of anti-vaxxers, those who refuse to have their children vaccinated without having valid medical reasons for such a refusal. 

After acknowledging that we have always had the conspiracy theorists, the flat-earthers, and the holders of other nutty theories among us, Bruni views today's anti-vaxxers as an example of wider problem with the refusal to accept facts:

But there are differences now that make the cranks that much more baffling, numerous and pernicious. For starters, they fly ever more stubbornly in the face of sophisticated research and hard-earned knowledge. Beneficiaries of wisdom that prior generations lacked, they toss it away, wasting and mocking progress itself.
At the same time, in many educational circles, there’s as much talk of students’ individual truths as of the truth.

Bruni continues:

There’s also a man in the White House, at the Resolute Desk, who makes grand pronouncements based on random conversations; implores Americans to distrust traditional institutions and conventional sources of information; and promotes conspiracy theories (millions of illegal votes, a celebration among Muslims in Jersey City on 9/11, and on and on). He has specifically echoed and validated the apprehensions of anti-vaxxers. Whether he’s symptom or cause doesn’t matter. He’s dangerous either way.
Then there’s the internet, which turbocharges everything.

I mostly agree with Bruni.  The role of the internet here is crucial.  It  allows someone to do "instant" research which might lead to various conspiracy sites, all swearing that they are the only ones producing true facts, and it also allows that same someone to find sites where other people with the bizarre views congregate and support each other in  those flawed opinions or biases.

It's not that received wisdom should not be criticized or that academic research is always flawless.  But to criticize established wisdom or academic studies, one needs to know what that established wisdom is, what it is based on and what might be right or wrong in the methodologies of the studies one finds suspicious.

Learning to do that kind of criticism is like learning any other skill.  It takes study and the right tools.  And right now those tools and teachings are too often replaced by a Google search.

The ironic aspect of the anti-vaxxers' distrust of medical science is that it sprouted from an academic 1998 study, a very flawed one, which connected childhood vaccinations with autism.  Despite repeated debunking of the study, the fear that vaccinations might cause autism is still a topic that crops up on the anti-vaxxer sites.

The above links the anti-vaxxing phenomenon to the wider purchase conspiracy theories have today, as a sign of the irrationality of our post-truth Trump times.

But the decision not to have one's children vaccinated can also be a rational one, though only on a narrowly selfish basis, at least as long as herd-immunity prevails

If almost all the other parents in the area have vaccinated their own children and if the custom of vaccination is old enough so that almost all adults in the community have immunity, too, then the benefits from vaccinating your own children become negligible.  Your child won't get infected!

But any kind of vaccination may have harmful, though rare side-effects.  The private (based only on one's immediate family) comparison of benefits from the vaccination to its costs, both financial and possible health risks, would strongly suggest that for one particular family the choice not to vaccinate can be rational*.

Given that you are smart and erudite, my dear readers, you have already spotted the logical flaw in the above calculations:  If not getting the shots is narrowly rational for the one family in the above example, then it is narrowly rational for all the other families, too!** 

But once a sufficient number of families chooses not to vaccinate, whoops!  The herd immunity is gone, the infectious diseases return to the communities, and there will be deaths and very high health care costs and unnecessary pain and suffering***.

This is what we are now seeing.  If decisions to forego vaccinations are based on those narrowly-rational-though-selfish reasons, realizing that the herd-immunity is disappearing should cause a change in those decisions.  If the reasons are more irrational, well, who knows what might happen****.

* This is similar to the "free rider" problem in economics, because the protection herd-immunity offers has the qualities of a public good.  Those who refuse the vaccinations will still be protected by the herd-immunity, as long as others get their children vaccinated.  The refusers are riding free on the bus the others are "paying" for by getting the vaccinations.

** I call the above rationality narrow and selfish, because it assigns zero value to the benefits that vaccinating the family's own children would provide because it also protects vulnerable  people outside that nuclear family.  The vaccinations are, of course, what creates the herd-immunity in the first place, but that benefit does not enter the private calculus.

***  The increased knowledge also applies to finding out why vaccinations against certain diseases were created to begin with.  Many of those diseases, such as tetanus, can be major killers.  I believe that the lack of personal knowledge of the havoc infectious diseases can do is part of the reason why so many view vaccinations as unnecessary.  My family history includes a tale of five children in the same nuclear family dying of diphtheria within one month in the early 1900s.  Such stories make the idea of not vaccinating children emotionally impossible to me.

****  To be fair to the anti-vaxxers, the pharmaceutical industry may not look too trustworthy, because is influenced by the profit motive even when the profit is derived in an unethical manner.  And there's a tendency among some medical researchers and many medical professionals to discount information the patients offer them.  This tends to lessen general trust in the medical profession and in medical studies.