Debates about vaccines are a recurring feature of contemporary politics. It turns out they actually date back more than 200 years, since the development of the first smallpox vaccine. MIT Professor Thomas Levenson, one of the countryâs leading science writers, explores this important history in a new book about the contours of anti-vaccination thought.
Levenson identifies different types of arguments vaccination opponents have developed through history, to help shed light on our current debates. He spoke with MIT News about his new book, "A Pox on Fools: The True Believers, Grifters, and Cynics Who Convinced Us to Reject Vaccines," published this week by Penguin Random House.
Q: Your book is about the longer history of anti-vaccination arguments. How far back does this go, and what have those arguments been?
A: Hesitation, skepticism, and outright opposition to vaccines is not a new thing. It didnât just happen starting in the late 1990s. Opposition to vaccines dates back to the beginning of the vaccine era, around the early 19th century. The first kind of opposition to vaccines is this sense that it violates the moral or the natural order. If you believed that God has authority over all of us and is mindful of everything, intervening in the disease process could seem blasphemous. In the early 19th century, the first true vaccine, the smallpox vaccine, used material from a related disease, cowpox, that doesnât cause human beings to fall ill but does provide immunity to smallpox. That shifted the initial focus on Godâs plans to the notion that vaccination â sticking some cow-stuff into people â violated the natural order. That sort of uneasiness is easily co-opted by a broader philosophy that says: If you align yourself with nature, you donât need to use vaccines. I want to emphasize that in the early history of the anti-vaccine movement, there were reasonable fears being expressed. That changes over time, because science advances and the mystery of vaccines falls away. Still, the current anti-vaccine movement includes an impulse we all have: We wish to be in control. I would never deny the value of exercise, sunlight, and sanitation, but they are not sufficient when you are faced with many pathogens, and thatâs what the modern anti-vaccine movement obscures.
Q: One section of your book explores the argument that vaccines have been actively harmful. What is that historical trajectory like?
A: The idea that vaccines are not just unnecessary but actively bad for you is certainly very contemporary, but it too goes back to the beginning of the vaccine era. The first true smallpox vaccine came into public use in 1798. Very soon afterward people started pointing to different harms. Most of them were spurious. They were just making things up or mistaking another infection that was already there. But there were some flaws in the early forms of vaccination. People thought it conferred life-long immunity, and that wasnât always the case. Additionally, people mistook syphilis infections for cowpox infections and transmitted syphilis to healthy people. There were maybe 750 cases in Europe. What is repeated over and over in the history of vaccination is that when problems became apparent, people found a way to address them. A problem with diphtheria antitoxin at the turn of the century led directly to the first U.S. regulatory body, the Division of Biological Controls. And when the first polio vaccine was released to the public in 1955, one of the five drug companies making it had shoddy production practices. Thousands got sick, a hundred died, and some were paralyzed. The flawed vaccine was identified after two weeks on sale and stopped cold, and that ended that particular problem. What came out of it was the development of an FDA vaccine division with teeth. This is an area where the rhetorical skill of the anti-vaccine movement is on display. Anything human beings do carries some risk. Anything you do medically. I had my hip replaced last year. That carries some risk, such as surgical site infections. Well, the risks of vaccines are incredibly small. The most common response is a sore arm the next day, and maybe feeling under the weather. There is extremely close control over manufacturing now. We have stories of great harm, but the various specific allegations of the last 30 or 35 years have proven to be incorrect. But thereâs a power to an anecdote versus statistics.
Q: This book raises an issue also explored in your last one, "So Very Small," that the sheer success of vaccines has, paradoxically, created a situation in which people take their effects for granted and find it easier to argue against them. Can you explain this phenomenon?
A: The reason that occurs is because vaccines have worked so brilliantly well. At the turn of the century, life expectancy was much lower, 47 years in the U.S. Several top causes of death were infectious diseases, and child mortality was high. Now, life expectancy is around 80 years in every developed nation, and child mortality is a tiny fraction of 1 percent. By 1970, you had almost a complete set of vaccines against what used to be called childhood diseases. And those diseases, up until extremely recently, had essentially disappeared. And thatâs amazing. In the 1950s, before the measles vaccine, for instance, everybody had an experience of what it meant to be at the mercy of waves of infection. But by the 1970s, that was no longer the expected, ordinary, common experience of raising kids. So weâve forgotten how unpleasant even an ordinary case of one of these diseases is that you recover from, much less the more severe problems and death. In 1952, there was the largest polio outbreak in U.S. history, and it was scary to let your kid go to the movies or a swimming pool. They could go to someoneâs birthday party, come back, and two weeks later start feeling muscle aches and a fever, and two weeks after that were maybe paralyzed, or dead. Then in 1955 the Salk polio vaccine came out. We donât live that way anymore. And so, because infectious disease seems like a nonexistent threat, vaccines, even with a tiny potential of harm, are made to seem worse because we donât realize what happens if we let our vaccine coverage lapse. Well, weâre starting to get a glimpse of it, because the measles rate in the U.S. is shooting up, and we see what happens when vaccine coverage wanes, and in particular, when we lose herd immunity. In every population, some people cannot be vaccinated: infants who are too young, some people who have had transplants and are on immunosuppressive drugs, or the elderly in whom sometimes immunity wanes. Some diseases are so infectious, and measles is famous for this, that about 95 percent of a population must be vaccinated or the disease spreads. If weâre not at that threshold, every newborn is at risk. We donât know what itâs like to live with the genuine risk and fear of those diseases. If you were born in 1970, youâre 56 now, and you literally never lived in a world where these diseases were common.
Q: One source of resistance to vaccines is not strictly medical, but political and philosophical at one level. This also has a lengthy history, it seems.
A: Another major theme of the anti-vaccination movement is to argue the question: Who has the right to say that somebody else must put something in their body? Again, all this is not new: In the mid-19th century, in the United Kingdom, there was a requirement that children be vaccinated against smallpox, and these mandates brought immediate opposition as an infringement of liberty. In 1850 the countryâs top doctor, John Simon, physician to the privy council in England, described the right that people claim against vaccination as the liberty of âomissional infanticide,â that you are killing kids by not protecting them. Where do I stand? This is a philosophical question. Does the state have the right to make me do something because it will make society as a whole safer? I think, âYes.â We live in societies, we depend on each other for all kinds of things, we arenât just atomized individuals. But I can understand those who say, âNo.â I just think itâs wrong. But itâs an argument thatâs winning in