More than 200 years ago, Edward Jenner performed an experiment
that laid the foundation for the eradication of smallpox and
transformed humankind's fight against disease. Smallpox
afflicted humankind as no other disease had done; its
persistence and diffusion were without parallel. The disease
brought down at least three empires. Generations watched
helplessly as their children succumbed to the disease or were
disfigured or blinded by it. Attempts were made to contain
smallpox by isolating its sufferers and, later, by using
variolation with varying degrees of success. However, the
definitive solution was not found until Jenner's work was done
at the end of the 18th century. Milkmaids who had developed
cowpox from contact with cow udders informed Jenner that they
were protected from the human form of the disease; he listened
to their folk wisdom and raised it to the status of scientific
fact. Jenner did not discover vaccination, but he was the first
to demonstrate that this technique offered a reliable defense