Smallpox inoculation reached England through a woman the disease had scarred

Inoculation was the work of old women. Every autumn, in September, once the great heat had passed, people gathered in parties of fifteen or so, and an old woman arrived with a nutshell full of smallpox matter: she opened a vein with a needle, put in as much as would sit on the needle's head, and bound the little wound with a bit of shell. The children played the rest of the day; on the eighth day a fever came, they kept to bed for two days or so, and then they were well. Montagu knew of no one who had died of it, and she decided to try it on her own little son.

English doctors, she wrote, were unlikely to help: smallpox earned them too much. Back home in 1721, she had the surgeon Charles Maitland inoculate her young daughter in front of physicians from the royal court. In the spring of 1722 Maitland inoculated the two daughters of the Princess of Wales. The pathologist Stefan Riedel credits her persistent advocacy for bringing the practice to England.

Harmless it wasn't. By Riedel's account, 2 to 3% of those inoculated died, started a new outbreak, or caught another disease from the procedure itself. Still, its death rate was ten times lower than that of smallpox caught the ordinary way. And the story began with old women who came round every autumn with a nutshell.