Deep into the night on Jan. 26, 1774, a boat of angry fishermen pushed off from the craggy point of Marblehead under a waxing gibbous moon.
At some point on their brief journey, they began to discern the low, black shape of their destination: Cat Island.
Their trip, a mere five weeks after the Boston Tea Party, ended in violence. Once on the island, the men slathered tar on a hospital, then set it alight and watched it burn, according to a Salem newspaper.
The private hospital had been built for inoculating colonists — wealthy colonists — against smallpox.
Those who could afford inoculation had been using the facility to become immune to the feared disease.
Inoculation — an old-timey practice of taking an infected scab or pus, and injecting it into a healthy body to build immunity — had existed in other parts of the world for generations. But it had only recently become part of an effective public health system in and around Boston.
"And meanwhile, the common people, the fishermen, the sailors in Marblehead, are still suffering from the disease," said Andrew Wehrman, author of The Contagion of Liberty: The Politics of Smallpox in the American Revolution.
The angry sailors weren't the equivalent of modern-day anti-vaxxers, Wehrman said. Nor were they superstitious about the procedure.
To the contrary, they saw getting inoculated as an act of liberty, Wehrman said — liberty from disease. And they were willing to burn down a hospital to make that point.
The common defense
Three weeks before the early April morning shots rang out in the Revolutionary War, Boston's locally elected town selectmen convened at Faneuil Hall. Despite the ominous timing, the meeting "had nothing to do with stamps or taxation or representation in Parliament or tea or hidden gunpowder," Wehrman said.
Instead, the official town minutes, today preserved by the Boston Public Library, reveal that the meeting was about the growing number of smallpox cases.
The colonial American government had been charged with protecting their communities against disease — a mandate selectmen took seriously. Residents viewed that as "a responsibility of government," Wehrman said, similar to how leaders should offer protection from other dangers.
Local law mandated that any smallpox cases be reported to the Boston selectmen. The selectmen then shared that data with the press, which alerted the public. It was a well-oiled epidemiology machine: inoculation, contact tracing, public notices, quarantine.
But cases had been growing, an indication that there was a chink in the armor.
"And at that meeting, it's reported that General [Thomas] Gage has covered up 38 cases of smallpox — that he's isolated them on a ship in the harbor but has not alerted the selectman previously," Wehrman said.
It did not sit well with Bostonians to discover that Gage, Britain's military governor in Massachusetts, had been skirting the laws the Americans had determined for themselves. Boston was ahead of England in terms of inoculation policy, a point of pride among locals.
"There's absolute outrage. These people are not following our rules. And it echoes with some of the things that the revolution itself is about: that we can govern ourselves better than the British. They're out of touch with our needs," Wehrman said.
A visible contagion
The day before July 4, 1776, when the Declaration of Independence was adopted by the Continental Congress, Boston made a declaration of its own: the city ordered a general inoculation. That meant anyone could enter Boston and receive the inoculation — but they had to stay in quarantine until the live virus had run its course.
Among those rushing into town to get inoculated were Abigail Adams and her children. She had been holding down the fort in Braintree while her husband, John, edited the country's founding documents in Philadelphia.
Remarkably, their letters survive. Today, preserved by the Massachusetts Historical Society, they paint a picture of a community desperate for salvation from smallpox.
In one, she describes the moment she heard the U.S. Declaration of Independence proclaimed from the balcony of the Old State House — after which "the Bells rang, the privateers fired, the forts and Batteries, the cannon were discharged, the platoons followed and every face appeard joyfull." At the same time, she was also freeing herself and her children from disease.
The Adams letters also reveal why they were desperate to protect themselves from smallpox: its grotesque symptoms were visible all around them — a sight unfamiliar to modern generations, thanks largely to the success of global vaccine programs.
In writing of a sick resident, John describes him as "no more like a man than he is like a hog or a horse, swelled to three times his size, black as bacon, blind as a stone."
The evidence wasn't limited to their eyes. Local officials collected scrupulous public health data comparing deaths from catching smallpox "in the natural way" (without inoculation) to those who died from the inoculation process.
"In the 1752 outbreak, for example, 5,567 people caught smallpox naturally ... There were 514 deaths — that's 9% [fatality rate]. There were 2,109 inoculations [and] 31 deaths. That's 1.5% [fatality rate]. So would you rather have a risk of 1.5% or 9% fatality?" said Kanisorn Wongsrichanalai, the chief historian at the Massachusetts Historical Society.
"They were keeping records, and John Adams would have been very aware of these records," he said.
A special ingredient
It's difficult to apply history to modern day; most scenarios are deeply nuanced, with too many extraneous factors to allow for a fair equivalence. Even so, Boston's early public health system relied on an essential ingredient lacking today: trust.
"People had the trust that their government was working for them in these very specific ways and providing for them to protect against external threats," said Andrew Wehrman.
"They liked the representation they were getting out of their own city government. They didn't mind their taxes going for the city selectmen that they could see working hard in their communities. But when they're paying these taxes that go to some distant government three thousand miles away? That's where they start asking questions about it," Wehrman said.
Another aspect of that trust between the selectmen and the press were in the newspaper clippings that revealed the tallies and names of sick people, usually delivered to them by the local selectmen.
They were clearly watching one another. The stakes were high, so they had high expectations of one another.
The common good
In the 1770s, American colonists bitterly disagreed on politics, class, religion and independence itself. By contrast, smallpox had a way of uniting them in resistance against a common enemy. They believed it was a government's main role to defend its people against enemies both foreign and domestic — disease included.
"This was a way to prevent the deadliest disease of mankind, a way to protect your spouse, your children, and your parents," said Wehrman.
The notions that government should "provide for a common defense" and "promote the general welfare" would later appear in the preamble to the United States Constitution — years after Bostonians held up their local smallpox policy as a defense against infectious disease.
The disease was infectious — but so was the notion that the people deserved protection against it.
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