History Of Vaccine Hesitancy, From Smallpox To Covid

Vaccine policy made national headlines last week when the Centers for Disease Control and Prevention's vaccine guidance committee met and scaled back recommendations around the COVID-19 booster and the combined MMRV shot. It's far from the first time government vaccine policies have sparked heated discussion; since at least the turn of the 20th century, the conversation around immunization has been fraught, with each era's cultural and political issues shaping attitudes about disease, individual rights, community obligations, parenthood and science itself.

Elena Conis, a UC Berkeley professor of journalism and history, chronicled this evolution in her 2014 book, Vaccine Nation: America's Changing Relationship With Immunization. In it, she tells the stories of various vaccines, from that polio in the 1950s to HPV in the 2000s, and how the historical context of each affected its adoption by the public. For instance, President John F. Kennedy authorized landmark federal vaccination funding during a moment when faith in science and technology was high, and the Cold War had made having a healthy nation of potential soldiers a priority. The national guidance to give the hepatitis B vaccine to infants, which the CDC's advisory committee debated just last week, was established in the 1990s against the backdrop of worries about AIDS and immigration.

In addition to recounting how public opinion and federal policy has changed, Conis also documents how the medical advancements of vaccines altered the ways Americans perceived the very illnesses the shots could prevent. Below, UC Berkeley News spoke with Conis about the history of pro- and anti-vaccine sentiment and how both public perception and government involvement have shifted over time.

UC Berkeley News: What are some key turning points that explain how we arrived at our current policies and attitudes about vaccines?

Elena Conis: From the middle of the 19th century to the end of it, U.S. cities and states started to create more boards of health, many of which were imbued with the power to require the vaccination of their local populations. For several decades, these laws and regulations were enforced sporadically and unevenly. By the turn of the 20th century, there were boards of health with this authority across the U.S. Smallpox was also spreading at an alarming rate. So there were more and more clashes at the local level as these boards of health attempted to enforce mandatory vaccination in the context of a growing anti-vaccine movement.

This led to a key turning point: In 1905, the U.S. Supreme Court ruled that states have the authority to enforce compulsory vaccination if it is in the interest of public health, and importantly, if it doesn't cause any harm to individuals. But that Supreme Court ruling ended up galvanizing anti-vaccine groups even more.

This marked a new phase in vaccination history: Groups opposed to vaccines focused on state government, advocating for either exemptions to existing laws or undoing compulsory vaccination entirely, which California did in 1921. What the public health profession did in response was say, "All right, compulsion wasn't working so well. Let's back off that and try to persuade people to get vaccinations instead."

That changed in the polio era - another turning point. U.S. scientists developed a vaccine to stop this infectious disease that had terrified the population for the previous several decades and had worsened in the 1940s and early '50s. When the polio vaccine came out in 1954, the U.S. public responded by saying they really wanted the vaccine, and they wanted the government involved to make sure everybody had access to it and it was safe. So at that point, starting with Kennedy and then Johnson, the federal government was invited to take on a new, larger role in vaccination policy.

Then, in the 1960s, research on vaccine-preventable diseases made it increasingly apparent that where there were vaccine mandates, there was less disease. A new era of mandates, focused on children, began in the late 1960s. By 1980, all the U.S. states had laws or regulations requiring children to receive recommended vaccines before entering school. This era, in turn, was followed by a resurgence of vaccine hesitancy and vaccine rejection, which continues right to this day.

What are the historical roots of today's anti-vaccine movement?

Since the first vaccine against smallpox was developed in the late 1790s, there have been debates about the optimal role of government in determining who should get vaccinated against what and when. There's a rough pattern: The more vaccines and the more force used to encourage or require vaccination's widespread adoption, the more resistance we see in the population.

Throughout much of the 19th century in the U.S., people mostly got vaccinated when they wanted to, often when epidemics loomed or raged. In the latter half of the 1800s, as the authority of the local government and boards of health started to accrue, the anti-vaccine movement in this country also started to gain momentum. That happened in large part through the influence of writers and thinkers from Europe who were decrying the compulsory vaccination laws there, calling them an affront to individual liberty.

But people with anti-vaccine views in the 19th century also circulated two other arguments. One was that vaccination was anti-religion, for those whose belief systems held that the body was best able to heal itself or that it was God's will to determine who would survive an illness and who wouldn't.

The other was a risk-based argument. Smallpox vaccination in the 19th century could literally save your life, but getting vaccinated also carried the risk of another infection, like syphilis, being transmitted with the vaccine. That was because smallpox vaccines came either from the pus of cows infected with cowpox or a related virus that protected against smallpox, or from the pus of another person who had been vaccinated. The smallpox vaccine and other "animal vaccines" of the time led to individual cases and larger outbreaks, some of them deadly and well publicized, in the late 19th and early 20th century.

In short, these religious, rights-based and risk-based objections to vaccination have been with us ever since.

You write about how anti-vaccine sentiment has drawn rhetorically from political movements across the map over time. Can you expand on that?

Even back in the 19th and early 20th century, the cause drew support from what we would now call politically liberal groups. Abolitionists sometimes supported the anti-vaccine movement, as did child safety and animal rights advocates.

The resurgence of vaccine skepticism a century later, in the 1970s, was characterized by rhetoric that borrowed from the environmental movement, the women's movement, the patient's rights movement and the consumer movement, among other social movements of the time. People talked about vaccines polluting the body, and they were worried about the ingredients in vaccines being similar to ingredients that they knew posed environmental dangers. They also argued that parents should have the right to informed consent before getting a vaccine for their children, an argument that borrowed directly from ideas popularized by the women's health movement.

Even though there is still a strong influence from libertarian ideology in contemporary anti-vaccinationism, one that traces back well over a hundred years, there are also roots in these liberal social movements.

How has our changing media ecosystem impacted attitudes toward vaccination?

Groups with strong opinions about vaccines have always used the media to circulate their ideas. That has not changed. What has changed recently is access to these ideas. All kinds of ideas about vaccination, including disinformation and misinformation, can circulate far more widely and quickly today than ever before.

But perhaps even more important is how polarized our current media environment is. Depending on your individual media habits, you're going to see one set of ideas about vaccines presented to you over and over in your news feeds or social media, or you'll see a completely different set. Which means that with every passing minute of our media consumption, the vast majority of us are becoming more entrenched in our views and less able to understand the views of people who think differently from us.

This interview has been condensed and edited for clarity.