History of Vaccines
It took many years for the medical community to accept Jenner's finding on smallpox.health and fitness Updated: Oct 08, 2003 21:53 IST
Even before the world of microorganisms was discovered and before diseases were associated with microorganisms, many societies had made one observation: if a person was down with a disease and survived, he was less likely to catch it again.
The Chinese tried to prevent smallpox by exposing healthy individuals to extract from lesions of smallpox patients. This process is called variolation. There are many forms of variolation.
Lady Mary Wortley Montagu, wife of the British Ambassador to Turkey, observed one of these processes in the early 18th century and brought this idea to England. Though this did not produce uniform success, variolated groups showed less incidence of smallpox. One of the children who underwent variolation was Edward Jenner who grew up to be a country doctor in England.
Jenner studied the relationship between a disease called 'grease' in horses and cowpox, an infection similar to but not as deadly as smallpox, in cows. One milkmaid told him that she was not afraid of contracting smallpox because she had already suffered cowpox.
Jenner thought about it, and made a daring experiment, an act that would be completely unacceptable today. He infected a boy with the cowpox lesion extract. When the boy recovered from this mild disease, he infected him with pus from a smallpox blister. The boy did not contract smallpox.
This was in 1796. But it took some years for the medical community to accept Jenner's finding.
First Published: Oct 08, 2003 21:53 IST