The Contagion of Liberty: The Politics of Smallpox in the American Revolution Andrew M. Wehrman Johns Hopkins Univ. Press (2022)

It took some work to convince the physicians of 1720s Boston, Massachusetts, that Onesimus, an enslaved Black man, might hold the key to overcoming an impending smallpox epidemic. As cases mounted, and with no other options, one doctor eventually decided to take a chance.

Onesimus had told his enslaver how people in Africa took material from the pustules of someone with the disease and stabbed it under the skin of others to protect them. This practice, later called variolation, had been used in some parts of the world for centuries, but was not widely embraced by Europeans.

His enslaver found a physician in Boston willing to give it a go. The result was an early step towards widespread inoculation, and towards the concept that governments have the responsibility to protect communities against infectious diseases.

In The Contagion of Liberty, historian Andrew Wehrman traces the path of the smallpox-inoculation movement, and its generally overlooked impact on politics around the American War of Independence. He argues that smallpox influenced the journey towards independence from British rule, and how Americans conceived of their new, hard-won liberties.

It is a tale of startling contemporary relevance.

Smallpox outbreaks were persistent in colonial America. But inoculations were controversial from the off. The process administered small amounts of live virus, triggering an infection that would probably be milder than a natural one, with the aim of conferring protection against future disease.

This procedure carried a small but significant risk of disability, scarring and death. And freshly inoculated people were a risk to their unimmunized neighbours: if not accompanied by rigorous quarantines and containment measures, inoculation against smallpox could itself trigger epidemics.

So the process was fundamentally a public affair. As revolutionary sentiment simmered, the colonies cycled through a series of smallpox outbreaks; each city mounted its own response. Wehrman recounts in exhaustive detail the debates and votes in a handful of towns as citizens grappled with when to allow inoculation, who should receive it and how it should be administered. At times, it’s hard to see where this is all heading.

Eventually, Wehrman’s point becomes clear. Riots over access to inoculation and public bickering about how it should be done give way to consensus as the fledgling nation emerges from war: smallpox inoculation saves lives, and the country’s new government should ensure that it is available. Communities discuss pre-emptive inoculations, systematically administered to all children rather than waiting for an outbreak. There is talk of trying to eliminate smallpox altogether.