title: An estimation of the impact of smallpox eradication on the expectation of life in selected less developed countries.
mesh_terms: D001938:Brazil; D003906:Developing Countries; D004812:Epidemiologic Methods; D006801:Humans; D007194:India; D008017:Life Expectancy; D008433:Mathematics; D009549:Nigeria; D012899:Smallpox / Q000517:prevention & control*