††An inoculation is an injection into the body of dead or weakened germs or their poisons. This encourages the body to develop a mild form of the disease and so makes it able to resist further attacks of that disease. The first inoculation was against smallpox. A British doctor, Edward Jenner, injected a boy with cowpox, a mild form of smallpox. When the boy was well again, Jenner exposed him to smallpox. The boy did not develop smallpox because the cowpox had made him immune. Similar methods of inoculation are used today against a number of other killer diseases.
