Steven Levitt made a great point on the Freakonomics podcast a while back that stuck in my brain. An interviewer asked him how to best go about persuading someone with statistics and data and he answered something like, "I think the first thing you have to do is decide why you want to persuade them so badly. Take a deep breath and decide if it's worth it to try."
Levitt expounded on this point on Brian Leher's show, saying of persuasion:
"We'd like to think we're all open minded people who assess the available logic and data and information we can and then kind of weigh it and decide how we want to think about it. But as a matter of fact, our biases are pretty strong and our preconceptions are pretty strong and we use a lot of shortcuts and we like to think the way other people in our circle think. So most people have an ingrained take on a particular topic and to try to budge them on that can be close to impossible."
This makes sense when he lays it out, right? Maybe we, the internet collective, pretend that we pen these thoughtful editorials designed to persuade, but we really just excel at rephrasing and packaging opinions that our readers already have? So, is it futile to try to convince people who strongly, innately disagree with you, who have absolutely, unshakably decided on their truths, who are not open to new evidence, whose friends all agree with them, and whose fingers are in their ears?
But I kept reading about this growing anti-vaccine movement and it kept making me feel queasy and impotent. And then I saw this wonderful satirical piece on The Daily Show which deftly handled the politics of it, so I decided go ahead and post about this because, for once, the consequences of not trying to persuade people about this are actually life-threatening.
The Daily Show clip explores a unique angle of this issue that's been a little under-discussed: the idea that the anti-vaccination movement was borne of the extreme Left. Usually, the people who are denounced as enemies of science are those on the extreme Right; generally, the conflict is between conservative religious priorities and "liberal" scientific ones. But this particular anti-science movement is unique in that it's rooted in leftism -- you know, Eastern medicine, anti-conformism, homeopathic remedies, ridding the body of toxins, distrust of Big Pharma, etc., etc. The conspiracy theories that birthed anti-vaxxers are wholly different than those that oppose stem cell research or global warming or teaching Evolution in schools. And the demographics of this movement make it unique in how mainstream science has to combat it.
To me, this movement is a prime example of the notion that both sides of the ideological spectrum can fall victim to extremism, and that extremism of any brand -- far Left or far Right -- tends to be sensational, unrealistic, divorced from fact. I was certain that logic and reason always hovered closest to the middle. But Levitt tells us that everyone thinks they are reasonable and unbiased; no one says "I am an extremist fundamentalism and that's why I don't believe in vaccines." They say "I have done the research and weighed the options and that's why I don't believe in vaccines." But how can that be true? Put otherwise: how do we persuade people who aren't relying on their "gut" or their "faith," but are relying, so they claim, on science itself?
By far the main reason cited by parents for refusing to vaccinate their children is a concern that certain vaccines may be linked to Autism. This claim has never been substantiated in the scientific or medical communities. Never. (The one scientific study positing a causal relationship between vaccinations and Autism was not only widely discredited, but in fact retracted by the scientific journal that published it. Furthermore, during an ethics investigation, the study's author was found to have conducted his research "dishonestly and irresponsibly." ) Arbiters of science and medicine have been falling all over themselves to test and retest and publish and republish this medical fact: there is no scientific link between vaccinations and autism.
Statements explaining the fact that science has found no link between vaccines and Autism -- and genuinely begging parents to vaccinate their children -- have been issued by such heavyweights as the Center for Disease Control, American Academy of Pediatrics, the World Health Organization, and the Institute of Medicine, in addition to thousands of other reputable rallying cries. There are no shortage of independent scientific studies on the subject, like this study and this one. The Autism Science Foundation shares links to more than 20 such studies on its website and advises parents, "[t]he results of studies are very clear; the data show no relationship between vaccines and autism." Even Autism Speaks, "the world's leading autism science and advocacy organization," formally states that "studies have not found a link between vaccines and autism," and "strongly encourage[s] parents to have their children vaccinated for protection against serious disease." This fact, this science, is not in dispute.
And yet, the medical community has been shockingly unsuccessful in persuading parents with these facts. So, what of it? As someone who is generally rather libertarian about personal health choices (well, maybe not?), I understand the inclination to let these anti-vaxxing parents make their own bad decisions: okay guys, "you do you" and all, feel free to lie in your own dirty, virus-y bed. But the egalitarian approach collapses when our freedom from outbreaks of contagious diseases depends largely on this thing called "herd immunity" to actually work.
Herd immunity: the idea that if a certain threshold of people (approximately 95%) are immune to a contagious disease, they will act to protect the disease-susceptible in the population from contracting it. It's a very careful balance and small dips in immunization rates can dramatically endanger the population at large. So, what happens if the balance tilts away from an immunized herd? Well, the anti-vaxxers are giving us a chance to see it in real time:
measles are back. Measles, a highly contagious and potentially deadly respiratory disease, was declared officially eradicated in the United States in 2000, meaning that the continuous spread of the diseased had been effectively stopped. This was a major public health victory that was accomplished through the use of vaccines. However, "between January 1 and November 29, 2014, there were 610 cases of measles nationwide — the highest number of cases since measles was declared eliminated in the United States in 2000." As of the CDC's April 2014 numbers, 68% of the unvaccinated measles cases had a 'personal belief' exemption from school vaccination requirements.
For those of you who've been watching the news, this includes a major outbreak at Disneyland just this week. As a result of one unvaccinated Disneyland-goer, 52 people have been diagnosed with measles after coming into contact with the virus at the park. Fifty-two, from one exposure! That's because "for every person infected with measles who enters a completely susceptible, unimmunized population, 12 to 18 people are infected." To put that in perspective, Severe Acute Respiratory Syndrome, aka "SARS," the epidemic that dominated the news in the early 2000s, when introduced to an unimmunized population, will only affect only 2-4 people. Ebola in the same population? Only 1.5 to 2.5 people. And we thought that was the public health crisis of the decade.
Second, the U.S. is on track to have the most severe whooping cough (pertussis) outbreak in a half-century. This graph scares the crap out of me:
In a real-life controlled test group study, a major outbreak of whooping cough has struck a Michigan county which has the highest rates of parents choosing not have their children vaccinated. One single school in this unvaccinated county has reported 151 cases of pertussis. It's the worst kind of "I told you so."
Look, I know I'm not a scientist or a medical provider or a parent, so I am woefully ill-equipped with either personal authority or anecdotes. But, these are raw numbers. This is the entire medical and scientific community imploring parents to vaccinate their children. The problem is, this information is only disseminated to people who look for it, like me -- that is, people who don't need to be convinced by it. The anti-vaccine rumors and gossip and hearsay, though, are transmitted rapidly, organically, person-to-person, unsubstantiated Facebook link by unsubstantiated Facebook link. Hysteria spreads like -- well, a virus -- and once the idea and the pseudo-science that supports it gets implanted, it's extraordinarily, terrifyingly difficult to persuade people of the truth.
At the end of the day, I bet I elicited a rousing cheer out of those of you who already agreed with me, and alienated those who didn't. If any passionate anti-vaxxers got past the title of this blog, I bet they spent the post teeming with comebacks and refutations. If not, I'd love to hear from you. That's because the problem with vaccines isn't the science; it isn't untested or unproved or up in the air. The problem with vaccines is persuasion. How do we get people to listen to something they don't want to hear? How do we get people who think they've made a rational, medically-sound choice to weigh the science on the other side? How do you talk somebody out of what they want to believe? I don't know, but we'd better figure it out.