[Health in Puerto Rico in the 20th century].

The evolution in physical condition, life expectancy at birth, and access to preventive and curative services rapidly improved the quality of life of Puerto Ricans in the twentieth century. The population quadrupled to almost 4 million inhabitants and the crude mortality rate fell from 38 per thousand in 1900 to 7.7 per thousand in 1997, with its most dramatic change (18.6 to 6.7) occurring from 1941 to 1960. The great promoters of health were the general increase in socioeconomic level, improvements in infrastructure, and vaccines; its great scourges were infectious diseases (from hookworm to AIDS) and social dislocations, such as the war of 1917 (accompanied by epidemics and hunger) or the present war between illicit drug distributors. This article summarizes the events in the century related to health and its political and economic contexts, the developments in public health structures and health care, professional education, volunteer organizations, campaigns against infectious diseases, chronic causes of mortality, and environmental problems. Bringing the capacity to defend public health to the level of sophistication available for clinical care is one of the vital challenges of the twenty-first century for Puerto Rico.