vaccine：来自一头牛的礼物

The word "vaccine" comes from vacca, the Latin word for cow. To understand why, we need to go back to an English country doctor in the 1790s. At that time, smallpox was one of the most feared diseases in the world. It killed huge numbers of people, especially children, and left many survivors badly scarred. Edward Jenner, a doctor in the English countryside, had heard an interesting piece of local wisdom. Milkmaids – women who milked cows – often caught a mild disease called cowpox from the animals. And people said that milkmaids who had had cowpox never caught smallpox. In 1796, Jenner decided to test the idea. He took some material from a cowpox sore on the hand of a milkmaid and put it into a small cut on the arm of an eight-year-old boy, James Phipps. The boy became slightly ill and then recovered. A few weeks later, Jenner exposed him to smallpox. The boy didn't get sick. (Today, of course, an experiment like this would never be allowed.) Jenner called his method "vaccination", from variolae vaccinae, the Latin name for cowpox, meaning "smallpox of the cow". Almost a hundred years later, the French scientist Louis Pasteur developed protection against other diseases, and he suggested using the word "vaccine" for all of them, in honour of Jenner. Thanks to vaccination, smallpox was completely wiped out in 1980. So every vaccine you've ever had owes a small debt to a cow.