Around 3 a.m. one November morning in 1721, a bomb crashed through the window of Cotton Mather’s Boston home. It had been hurled with such force that the fuse fell off, and it failed to detonate. Attached to the explosive was a warning note: “Cotton Mather, you dog, dam you: I’ll inoculate you with this; with a Pox to you.’’

The would-be bomber was not angry over politics, or love, or a business deal gone wrong, but rather over Mather’s attempts to save Boston residents from one of the deadliest threats of the era: smallpox. The same Puritan minister who played a role in fueling the execution of 14 women and six men during the Salem witch trials was now calling for the use of an experimental new way to prevent disease. Mather supported inoculation, a precursor to vaccination.

Nearly 300 years later, doctors are working to develop a vaccine for coronavirus — an infection far less lethal than smallpox — as people around the world clamor for treatment.

In the 18th century, however, Boston’s colonists met Mather’s inoculation proposal with a terror that bordered on hysteria. They didn’t understand how inoculation worked, and the notion of choosing to infect yourself with a deadly disease struck them — perhaps understandably — as outrageous. Fear of science, suspicion of the ruling elite, and a belief that medicine might meddle with God’s will — these ideas guided the angry mobs in Boston in 1721 and linger today in some form in anti-vaccine movements.

The 1721 smallpox epidemic in Boston began with a single sailor exhibiting signs of the disease, and within a few months, nearly half of the city’s 11,000 residents fell ill. Hundreds of deaths followed. The tolling of Boston’s 10 church bells was so constant that the town selectman was forced to limit a single bell toll per death. Panic gripped the city where everyone lived in fear of seeing the telltale rash appear on their skin.

Mather, then 58 and one of Boston’s best-known men, had learned of a smallpox inoculation process through his slave, Onesimus. The minister was so convinced by Onesimus’s description of the inoculation he had undergone in Africa — scraping a piece of smallpox pus and inserting it under the skin of a healthy person — that he convinced local physician Zabdiel Boylston to inoculate two more slaves and Boylston’s own son. After the process worked, Mather became a public crusader for the cause of inoculation, igniting a fierce debate over inoculation, public health and the role of local leadership in epidemics. The fact that Onesimus came from Africa only stoked racist fears about exotic sorcery.

Much like anti-vaxxers of today, dissidents came from a wide variety of education levels and socioeconomic backgrounds and could not fit easily into a single category. William Douglass, the man leading the anti-inoculation charge, was one of the few Boston doctors with a medical degree. The public debate that ensued drew on scripture and suspicion but also on practical argument: Douglass pointed out that inoculation (unlike modern vaccines) remained untested and that Mather and Boylston’s experiments hardly held up to scientific scrutiny.

Like today, too, critics of inoculation did not have faith in those in power. “Where I see the most commonality is a mistrust in leaders: both civic leaders, religious leaders and in scientists,” said Andrew Wehrman, an assistant professor at Central Michigan University specializing in the politics of medicine in early America. He went on to list the many differences, including how quickly people would come to change their minds. In just a few short decades, he noted, some Revolutionary War soldiers would be using their enlistment bounties to pay for their own inoculation.

There was a religious element, too. Some who opposed inoculation spoke of the practice as a violation of God’s will as well as doing specific harm to innocent people. Mather too, drew on comparisons to God and Satan in understanding the epidemic. Instead of saying the people of Boston were simply mistaken, he wrote in his diary that the devil had “taken a strange Possession” of them.

Massachusetts in 1721 was a place of paradox, deeply rooted in superstition. Dozens of people had been accused of witchcraft more than 30 years before, not just in Salem but in several towns across colonial Massachusetts. In Andover, nearly 1 in 10 residents would be accused of witchcraft.

“Boston was a small and almost insular city — it isn’t quite an island, but it almost is. It’s connected by a thin peninsula to the mainland,” said Ted Widmer, a history professor at CUNY who has studied this outbreak.

At the same time, Massachusetts residents were also exhibiting a growing interest in learning and in science. Harvard was 85 years old at the time, and Boston would soon become home to a growing number of higher education schools and prominent scholars. As a dogmatic Puritan with an interest in science, Mather epitomized these two strains of thought that were wrestling for dominance.

“It’s as if Jerry Falwell were also studying quantum physics,” quipped Widmer.

Attitudes toward inoculation changed quickly over the next two decades. During the American Revolution, pleas for inoculation became a kind of parallel struggle for independence, according to Wehrman, with people demanding to be free from disease as well as tyranny.

Part of the difference in the acceptance of inoculation within a short few decades was the visibility of its results. Smallpox was so prevalent in 18th- century America that nearly everyone would either contract the disease during their lifetime or know someone who would.

By comparison, the vast majority of 21st-century Americans have neither contracted the mumps, measles, or rubella, nor do they know someone who has, making it harder for them to understand the consequences of not vaccinating. Anti-vaccine sentiment plummeted in the mid-20th century, when a new polio vaccine came out shortly after a polio epidemic in the United States. Depending on how the coronavirus epidemic plays out, it could have an impact on public attitudes toward vaccination.

There are many distinctions between the anti-vaxxers today and those angry mobs in 18th-century Boston. One of the most interesting, however, may have been their ability to change their minds. After Mather and Boylston published their inoculation results in local newspapers, Douglass and other prominent critics of the practice publicly reversed their positions. Douglass even started performing inoculations himself.

Jess McHugh writes about the intersection of history and culture. Her work has appeared in the New York Times, Time magazine and The Paris Review, among others.

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