Fifty years ago, good health in Asia meant merely surviving. Malnutrition was widespread, and so were diseases associated with poverty: cholera, dysentry, typhoid and parasitic infections. In 1955 the average life expectancy was 48 years; by 1995 it had climbed to 65 years. Some Asian countries enjoy even higher numbers. Japanese now lead the world in longevity, with women enjoying an average life expectancy of 83 years. Some diseases have been eradicated through concerted programs of relatively cheap immunization.