After watching doctors struggle to cure a boy bitten by a rabid dog, the ancient Roman historian Aelian wondered if a cloth bitten by the same dog could be used to transfer the disease at will. His idea, it turns out, is just one of the first in a long line that go, “Hey, I wonder if we could give this horrible disease to our enemies.”
Sure enough, historical detective work uncovers two intriguing formulas for creating biological weapons in an ancient Indian manual of warfare. The Arthashastra by Kautilya (fourth century BC) tells how to make many different types of poison arrows.
One recipe calls for mixing various toxins with the blood of a musk rat. “Anyone pierced with this arrow,” wrote Kautylia, “will be compelled to bite ten companions, who will each in turn bite ten more people.” The implication is that musk rats were a vector of rabies in India.
The other poison arrow recipe calls for “the blood of a man and a goat to induce biting madness,” which sounds suspiciously like rabies. Perhaps goats were susceptible to rabid animal bites.