This essay is adapted from the podcast Pessimists Archive. Its new episode is about the history of the anti-vaccine movement, and features Tonic's very own managing editor, Mike Darling.
The anti-vaccine movement is as old as the vaccine itself—which is to say, it dates to the 1700s. Back then, skepticism was understandable: Medicine was a shaky combination of science of guesswork, and the earliest vaccine was nothing more than an intentional infection of cowpox, a lesser form of smallpox. Then medicine improved. The vaccine became ever-safer, saving countless lives across the world. "One might suppose," wrote someone in the New York Times in 1875, "that the popular prejudice against vaccination had died out by this time."
Now, 142 years later, the "popular prejudice" may be weakened, but it has hardly died out. Vaccines prevent the deaths of about 2.5 million children every year, but Donald Trump has embraced long-discredited theories linking vaccines to autism, measles has repeatedly broken out among unvaccinated people in Minnesota, and there was even an anti-vaccine march in Washington this year. To most people, for whom vaccines are just a normal part of healthcare, the ongoing fight seems flat-out confusing. What are these people fighting against?
To understand, it's worth rewinding back to one of the earliest vaccine fights in America. It's largely forgotten by history books, but may also be one of the most illuminating. And it nearly cost a doctor his life.
In 1901, Boston was trying to fight off a smallpox outbreak by encouraging everyone in town to get vaccinated. An increasingly vocal anti-vaccine movement rose up to fight this. By November, the fed-up chairman of the board of health issued a challenge: If any adult anti-vaxxer wanted to truly stand by their beliefs, he wrote, "I will make arrangements by which that belief may be tested." He'd expose them to smallpox. Then everyone could see what happens.
It took a few months, but someone stepped forward to take the challenge. His name was Immanuel Pfeiffer, and he was a local doctor who advertised his abilities to cure "all kinds of chronic diseases by the simple laying on of hands." Vaccines were unnecessary, he claimed. And so off he went to tour Gallop's Island, where smallpox patients were being quarantined. Then he came home and, to perhaps nobody's surprise but his own, he became sick with smallpox. The case became national news, and the New York Times reported that Pfeiffer "probably will die."
And yet a month later, in March of 1902, newspapers reported a crazy plot twist: Pfeiffer survived! Not only that, but he was recovering nicely. His son, Immanuel Jr., took a victory lap for his dad in the press, issuing this statement: "Dr. Pfeiffer is as strongly opposed as ever to vaccination. Nothing has happened to change my own views on the subject, and I am as earnest as my father in opposition to vaccination." And Dr. Pfeiffer would go on to live decades longer.
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It also seems that he inspired other activists. That same year, smallpox broke out in nearby Cambridge and the city mandated vaccines. Doctors went door-to-door administering them. But when they reached a preacher named Henning Jacobson, he refused to be treated. The city fined him $5 (or about $100 in today's dollars), he appealed, the anti-vax movement got behind Jacobson, and the fight made its way to the US Supreme Court. Jacobson argued that mandatory vaccines violated his personal liberty; the state argued that when the entire public's health is at risk, the welfare of the whole trumps the rights of the individual. In 1905, the court sided with Massachusetts: States can mandate vaccines. Anti-vaccine activists have been campaigning against this ever since.
The Supreme Court case may have had the lasting legal impact, but I'd argue that Pfeiffer's case is really the more insightful one. It gives us the greatest insight into the deep chasm between science and belief.
Anti-vaxxers are often motivated by what they've seen themselves. "I actually had long conversations with some anti-vax people," says George Annas, director of the Center for Health Law, Ethics & Human Rights at Boston University. "Because many of them had experiences with their children where they seemed to change radically right after they get vaccinated and ultimately were diagnosed as autistic. And yeah, you can tell that the vaccination had nothing to do with it. And scientists can say that it was coincidental. But you're not going to convince many mothers who have experienced that."
This is what carries through the history of vaccination debate: People base their fears, their knowledge, and their deeply rooted beliefs in what they personally experience. It's hard to value any information over that—even if it's the product of random chance, or goes against what all mainstream science says is possible. Because when a man is told that he needs to be vaccinated, and in response he basically bathes himself in a disease, catches it, and then survives, how do you tell that man that he's wrong? Even if he is wrong. Even if every expert, people who have devoted their entire lives and careers to a subject, all tell him he's wrong. Even if, had he done it all over again, that same stunt would have put him in a grave?
Nobody could yell or shame or make fun of Immanuel Pfeiffer enough for him to doubt what he himself lived through. Why even try? Sure, it would be tempting and emotionally satisfying to knock the guy, but it doesn't serve the greater good. Because the greater good is vaccinations. So that just leaves us with a question, the riddle to this problem that's lasted hundreds of years: How do you convince a person to believe something other than what they think they experienced themselves?
Solve that, and we're all cured.
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