Local Legend: From Myth to Legend (3)
Jenner had noticed that when he was variolating people the majority of them showed signs, however mild, of the illness; milkmaids did not. The penny dropped for him when treating milkmaid Sarah Melmes, for small pox like marks which appeared on her hands, and on the udders of the cows she milked. Jenner reasoned that because she had been infected with vaccinia, or cow pox, which was harmless to humans, she was immune to the life threatening human strain.
Vaccines
Jenner coined the word vaccine from the Latin vacca for cow, and called the process vaccination.
Jenner went on to prove his hunch, by carrying out an early clinical trial on the eight-year-old son of his gardener, James Phipps. James was infected with cow pox, became mildly ill, then when well again, he was infected with smallpox, and showed no sign of illness whatsoever.
Jenner felt he had discovered a cure for his "Speckled Monster", but now he needed the rest of the world to know about it.
