On Friday, the man who rid the world of smallpox died.
A doctor and epidemiologist, he joined the WHO smallpox program amd developed the concept of the ring inoculation - the focus lay on identifying and inoculating the contacs of infected persons first, doing surveillance on them and inoculation their contats, in turn, if one of them fell ill.
With 2.4 billion inoculation doses and 200,000 helpers, he spent 300 million before the last smallpox case in 1977 and the declaration that the world was free of smallpox in 1980.
I say this was a life well lived, and a very, very good deal for the world.