Historical Aside: An Inquiry Into the Causes and Effects of the Variolæ Vaccinæ, Or Cow-Pox

I found this writing by Edward Jenner recently, and also read it. It's actually sorta fun to read, with much more flowery language than you would find in any scientific or medical publication these days.

"The wolf, disarmed of ferocity, is now pillowed in the lady’s lap. The cat, the little tiger of our island, whose natural home is the forest, is equally domesticated and caressed. The cow, the hog, the sheep, and the horse, are all, for a variety of purposes, brought under his care and dominion."

If you've forgotten, Jenner is credited with discovering a vaccine against smallpox, by observing that farm workers who were involved with milking cows sometimes caught a mild disease called cowpox from the cows, and that those who came down with cowpox were thereafter protected from smallpox (a much more serious infection).

"It commonly happens that a disease is communicated to the cows, and from the cows to the dairymaids, which spreads through the farm until the most of the cattle and domestics feel its unpleasant consequences. This disease has obtained the name of the cow-pox.

"Morbid matter of various kinds, when absorbed into the system, may produce effects in some degree similar; but what renders the cow-pox virus so extremely singular is that the person who has been thus affected is forever after secure from the infection of the small-pox; neither exposure to the variolous effluvia, nor the insertion of the matter into the skin, producing this distemper."

In this article, Jenner presents a number of cases he has observed in support of this observation, including some children that he intentionally inoculated with cowpox. It's worth a read.

Something that makes it a little more interesting is the context of these observations. First, Jenner wrote that he always observed cowpox coming from a disease of horses' heels called "the grease," or from other cows with the pox. But there's a note from the editor in this article saying this hypothesis has since been shown incorrect. So not everything that Jenner observed was accurate.

Secondly, inoculating people with something related to smallpox was not something that Jenner invented. People had been introducing small amounts of smallpox into the skin (what Jenner here refers to as "variolous matter") in order to induce an immune response without a full-blown smallpox infection, for a while before Jenner. It tended to be unpleasant and somewhat risky, but usually preferable than catching smallpox the "natural" way. And if Jenner and other doctors of the time were right, the technique of introducing it into the skin mattered a lot in how safe it was. But what Jenner did contribute was using cowpox instead of smallpox for this inoculation, which was much safer. Henceforth this was called "vaccination," related to the Latin for cow (vacca), and the virus that caused cowpox was later called "vaccinia," though they didn't yet know what kind of thing it was yet.

I know back then there were plenty of negative feelings about vaccination (see here), but it seems like if something similar to what Jenner did were introduced today as an alternative to the modern vaccine schedule, many anti-vaccine people might be much more positively inclined toward it ("natural" immunity, no toxic ingredients, etc), which strikes me as sorta ironic.