English physician who pioneered vaccination. In Jenner's day, smallpox was a major killer. His discovery in 1796 that inoculation with cowpox gives immunity to smallpox was a great medical breakthrough. Jenner observed that people who worked with cattle and contracted cowpox from them never subsequently caught smallpox. In 1798 he published his findings that a child inoculated with cowpox, then two months later with smallpox, did not get smallpox. He coined the word ‘vaccination’ from the Latin word for cowpox, vaccinia . Jenner was born in Berkeley, Gloucestershire, on 17 May 1749, the son of a vicar. He was educated locally and in 1761 apprenticed to a surgeon in Sodbury. In 1770 he went to London to study anatomy and surgery under John Hunter, who took Jenner as his first boarding pupil at St George's Hospital in London. Hunter believed strongly that doctors could improve their treatments if they watched their patients and their surroundings closely, and taught Jenner the importance…