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This Day in History: An early form of biological warfare?

On this day in 1775, Americans receive a report that the British were working to spread smallpox among their ranks. Was it an early form of biological warfare?

Smallpox was a major problem during the American Revolution. The Army Heritage Center Foundation explains: “Because smallpox was common in England, most British soldiers had already been exposed and were immune, but the disease was less common in America and the average Continental Soldier was not.”

Interestingly, George Washington was an exception to this general rule. He’d caught smallpox as a young man and was thus immune. Was this the work of a divine hand, as some have speculated?

On December 3, an American officer reported that “four deserters have just arrived at head-quarters, giving an account that several persons are to be sent out of Boston, this evening or to-morrow, that have been lately inoculated with the small-pox, with design, probably, to spread the infection . . . .”

Could the British really be perpetuating such an “unheard-of and diabolical scheme”?

Washington didn’t believe it at first, telling John Hancock that “the information I received that the enemy intended Spreading the Small pox amongst us, I coud not Suppose them Capable of.” He changed his mind when smallpox began showing up on “Severall of those who Last Came out of Boston.” He reported to Hancock that “every necessary precaution has been taken to prevent its being Comunicated to this Army, & the General Court will take Care, that it does not Spread through the Country.”

At this point, the main coping mechanism was to isolate the disease. Inoculation for smallpox was different from the childhood vaccines that are so common today. It improved a person’s chances of survival, but it also guaranteed a milder case of the smallpox and sickness for a time. Those inoculated needed to be isolated; otherwise, they could spread the disease to others.

An inoculation performed incorrectly could start an epidemic of its own.

Unsurprisingly, then, Washington was reluctant to order inoculations. What if too much of the army was sick simultaneously? “I am much at a loss what Step to take to prevent the spreading of the smallpox,” he wrote in February 1777, “should We innoculate generally, the Enemy, knowing it, will certainly take Advantage of our Situation.”

In the end, Washington reversed himself. He couldn’t have the Revolution fail over a disease. His February 1777 letter concluded with a P.S. that contradicted his earlier statement. “Since writing the above,” he concluded, “I have come to the Resoluto. of Innoculatg the Troops, and have given Orders to that purpose . . . . This is the only effectual Method of putting a Period to the Disorder.”

Some have compared Washington’s order to the mandates being ordered in so many parts of the country today, but there are important distinctions.

First, the mortality rate for smallpox was quite high: 30%. The risk-benefit calculation that Washington undertook would have been different from the pros-cons being weighed today. Second, those who had already recovered from smallpox wouldn’t need the inoculation. The General himself was in this boat.

Finally, and most importantly, Washington’s order was issued before our Constitution was written. We don’t know what Washington would have done today. We know only that he found a military directive permissible during a time of war before the Constitution and its Bill of Rights were ratified.

We hear about the tragic or heroic deaths in battles. We hear far less about the more basic problem of humans grappling with disease. And yet it was a big problem for Washington and his army, too.

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