On Immunity: An Inoculation

by Eula Biss

If we imagine the action of a vaccine not just in terms of how it affects a single body, but also in terms of how it affects the collective body of a community, it is fair to think of vaccination as a kind of banking of immunity. Contributions to this bank are donations to those who cannot or will not be protected by their own immunity. This is the principle of herd immunity, and it is through herd immunity that mass vaccination becomes far more effective than individual vaccination.

Any given vaccine can fail to produce immunity in an individual, and some vaccines, like the influenza vaccine, are less effective than others. But when enough people are vaccinated with even a relatively ineffective vaccine, viruses have trouble moving from host to host and cease to spread, sparing both the unvaccinated and those in whom vaccination has not produced immunity.

The unvaccinated person is protected by the bodies around her, bodies through which disease is not circulating. But a vaccinated person surrounded by bodies that host disease is left vulnerable to vaccine failure or fading immunity. We are protected not so much by our own skin, but by what is beyond it. The boundaries between our bodies begin to dissolve here.

Herd immunity, an observable phenomenon, now seems implausible only if we think of our bodies as inherently disconnected from other bodies. Which, of course, we do.

The belief that public health measures are not intended for people like us is widely held by many people like me. Public health, we assume, is for people with less—less education, less-healthy habits, less access to quality health care, less time and money.

The concept of a “risk group,” Susan Sontag writes, “revives the archaic idea of a tainted community that illness has judged.”

when smallpox arrived in Middlesboro, Kentucky, everyone in the black section of town who resisted vaccination was vaccinated at gunpoint.

Unvaccinated children, a 2004 analysis of CDC data reveals, are more likely to be white, to have an older married mother with a college education, and to live in a household with an income of $75,000 or more—like my child.

Undervaccinated children, meaning children who have received some but not all of their recommended immunizations, are more likely to be black, to have a younger unmarried mother, to have moved across state lines, and to live in poverty.

when relatively wealthy white women vaccinate our children, we may also be participating in the protection of some poor black children whose single mothers have recently moved and have not, as a product of circumstance rather than choice, fully vaccinated them.

Viruses must enter and inhabit a living cell in order to reproduce, or to do much of anything. On their own, they are little more than minuscule bits of inert genetic material, so small that they cannot be seen by an ordinary microscope. Once inside another cell, viruses use that cell’s body to make more of themselves. The metaphor of a factory is often used to describe how viruses work—they enter a cell and force its equipment to produce thousands more viruses. But viruses strike me as more supernatural than industrial—they are zombies, or body snatchers, or vampires.

A virus can, on occasion, infect an organism in a way that ensures the viral DNA will be passed on to that organism’s offspring as part of their genetic code. A rather surprising amount of the human genome is made up of debris from ancient viral infections.

The cells that form the outer layer of the placenta for a human fetus bind to each other using a gene that originated, long ago, from a virus.

Our own adaptive immune system, the branch of our immune system that develops long-lasting immunity, is thought to have borrowed its essential technology from the DNA of a virus.

Some of our white blood cells combine and recombine their genetic material like random number generators, shuffling their sequences to create an immense variety of cells capable of recognizing an immense variety of pathogens. This technology was viral technology before it was ours. Of humans and viruses, the science writer Carl Zimmer observes, “There is no us and them.”

“Perceptions of risk—the intuitive judgments that people make about the hazards of their world,” the historian Michael Willrich observes, “can be stubbornly resistant to the evidence of experts.” We do not tend to be afraid of the things that are most likely to harm us. We drive around in cars, a lot. We drink alcohol, we ride bicycles, we sit too much. And we harbor anxiety about things that, statistically speaking, pose us little danger. We fear sharks, while mosquitoes are, in terms of sheer numbers of lives lost, probably the most dangerous creature on earth.

Paul Slovic, author of The Perception of Risk. In a study that invited people to compare various causes of death, Slovic found that people tended to believe that accidents cause more deaths than disease and that homicide causes more deaths than suicide, when the opposite is true in both cases. In another study, people significantly overestimated the fatality rates of highly publicized or dramatic dangers like cancer or tornadoes.

Our fears are informed by history and economics, by social power and stigma, by myths and nightmares. And as with other strongly held beliefs, our fears are dear to us. When we encounter information that contradicts our beliefs, as Slovic found in one of his studies, we tend to doubt the information, not ourselves.

Bicycles, the New York Times reports, “are involved in more accidents than any other consumer product, but beds rank a close second.”

“Perhaps what matters,” Sunstein muses, “is not whether people are right on the facts, but whether they are frightened.”

Paranoia, the theorist Eve Sedgwick observes, tends to be contagious. She calls it a “strong theory,” meaning a wide-ranging, reductive theory that displaces other ways of thinking. And paranoia very frequently passes for intelligence.

As Sedgwick observes, “to theorize out of anything but a paranoid critical stance has come to seem naïve, pious, or complaisant.”

Slovic suggests that people who are not toxicologists may apply a “law of contagion” to toxicity. Just as brief exposure to a microscopic virus can result in lifelong disease, we assume that exposure to any amount of a harmful chemical will permanently contaminate our bodies.

Fear of contamination rests on the belief, widespread in our culture as in others, that something can impart its essence to us on contact. We are forever polluted, as we see it, by contact with a pollutant. And the pollutants we have come to fear most are the products of our own hands. Though toxicologists tend to disagree with this, many people regard natural chemicals as inherently less harmful than man-made chemicals.

We seem to believe, against all evidence, that nature is entirely benevolent.

the idea that our medicine is as flawed as we are is not comforting. And when comfort is what we want, one of the most powerful tonics alternative medicine offers is the word natural. This word implies a medicine untroubled by human limitations, contrived wholly by nature or God or perhaps intelligent design.

What natural has come to mean to us in the context of medicine is pure and safe and benign. But the use of natural as a synonym for good is almost certainly a product of our profound alienation from the natural world.

Vaccination is a kind of domestication of a wild thing, in that it involves our ability to harness a virus and break it like a horse, but its action depends on the natural response of the body to the effects of that once-wild thing.

The antibodies that generate immunity following vaccination are manufactured in the human body, not in factories.

“Probably the worst thing that ever happened to malaria in poor nations,” Rosenberg writes, “was its eradication in rich ones.”

Matthew Bonds, an economist at Harvard Medical School, compares the global effects of disease to widespread crime or government corruption. “Infectious diseases,” he says, “systematically steal human resources.”

Even as Carson proposed that DDT could cause cancer, she recognized its utility for disease prevention. “No responsible person,” she wrote, “contends that insect-borne disease should be ignored.” Chemicals should be used in response to real threats, she suggested, rather than “mythical situations.”

VACCINATION IS A PRECURSOR TO MODERN MEDICINE, not the product of it. Its roots are in folk medicine, and its first practitioners were farmers.

variolation, the practice of purposefully infecting a person with a mild case of smallpox in order to prevent more serious illness, was still somewhat novel in England but had been practiced in China and India for hundreds of years. Variolation would ultimately be brought to America from Africa. The procedure was explained to the Puritan minister Cotton Mather by his Libyan slave Onesimus. When Mather asked him if he had ever had smallpox, Onesimus replied, “Yes and no.” What he meant is that he had been inoculated with smallpox as a child, like many other slaves born in Africa.

“If you want to understand any moment in time, or any cultural moment, just look at their vampires,” says Eric Nuzum, author of The Dead Travel Fast.

Wealthier countries have the luxury of entertaining fears the rest of the world cannot afford.

Immunity is a public space. And it can be occupied by those who choose not to carry immunity. For some of the mothers I know, a refusal to vaccinate falls under a broader resistance to capitalism. But refusing immunity as a form of civil disobedience bears an unsettling resemblance to the very structure the Occupy movement seeks to disrupt—a privileged 1 percent are sheltered from risk while they draw resources from the other 99 percent.

That so many of us find it entirely plausible that a vast network of researchers and health officials and doctors worldwide would willfully harm children for money is evidence of what capitalism is really taking from us. Capitalism has already impoverished the working people who generate wealth for others. And capitalism has already impoverished us culturally, robbing unmarketable art of its value. But when we begin to see the pressures of capitalism as innate laws of human motivation, when we begin to believe that everyone is owned, then we are truly impoverished.

The idea that the customer is always right, imported to medicine, is a dangerous dictum. “If you keep telling people that it’s just a marketplace and that they’re just clients and that the autonomy of the patient is what must be served to make them happy customers,” the bioethicist Arthur Caplan warns, “then you have a collapse of professionalism in the face of consumer demand.”

A popular alternative to vaccination in the nineteenth century was variolation, the practice of purposefully infecting a person with a mild case of smallpox. Both vaccination and variolation had their dangers. Both could cause high fevers, both could result in infection, and both could pass diseases like syphilis. But variolation, which produced an illness that tended to be fatal in about 1 to 2 percent of its cases, was more dangerous than vaccination.

THE CONCEPT OF CLEAR AND PRESENT DANGER was once used to defend mandatory vaccination in times of epidemic. And the term conscientious objector, now associated primarily with war, originally referred to those who refused vaccination.

One of the mercies of immunity produced by vaccination is that a small number of people can forgo vaccination without putting themselves or others at greatly increased risk. But the exact number of people this might be—the threshold at which herd immunity is lost and the risk of disease rises dramatically for both the vaccinated and the unvaccinated—varies depending on the disease and the vaccine and the population in question. We know the threshold, in many cases, only after we’ve exceeded it. And so this puts the conscientious objector in the precarious position of potentially contributing to an epidemic.

Our contemporary belief that we inhabit only one body contained entirely within the boundaries of our skin emerged from Enlightenment thinking, which celebrated the individual in both mind and body.

Vaccines are regulated, recommended, and distributed by the state—there is a very literal relationship between government and vaccination. But there is a metaphoric relationship too. Vaccines govern the immune system, in the sense that they impose a particular order on it.

We resist vaccination in part because we want to rule ourselves.

If our sense of bodily vulnerability can pollute our politics, then our sense of political powerlessness must inform how we treat our bodies.

If we understand ourselves as living in a world of unseen evils, the immune system, that largely conceptual entity devoted to protecting us from invisible threats, will inevitably take on an inflated importance and a distorted function. “The imperilled ‘immune system,’” the physician Michael Fitzpatrick observes, “is a metaphor for the prevailing sense of the vulnerability of the human individual in a hostile world.”

AIDS reveals that our immune systems are vulnerable to sabotage and can be permanently disabled. Vaccines, which engage the immune system, are now suspect as potential saboteurs, capable, we fear, of producing autoimmune diseases or overwhelming a child’s immune system.

For centuries before the word virus was first used to describe a specific type of microorganism, it was used more generally for anything that spread disease—pus, air, even paper. Now a bit of computer code or the content of a website can be viral. But, as with the kind of virus that infects humans, this content cannot reproduce without hosts.

Misinformation that finds a host enjoys a kind of immortality on the Internet, where it becomes undead.