The burden of chronic disease.

The shift from acute infectious and deficiency diseases to chronic noncommunicable diseases is not a simple transition but a complex and dynamic epidemiological process, with some diseases disappearing and others appearing or reemerging. The unabated pandemic of childhood and adulthood obesity and concomitant comorbidities are affecting both rich and poor nations, while infectious diseases remain an important public health problem, particularly in developing countries. More attention should be given to the high burden of disease associated with soil-transmitted helminths and schistosomiasis, which until recently was not considered a priority even though regular drug treatment is obtainable at relatively little cost. In developing countries, the pressing requirement is to provide an accessible and good quality health-care system, whereas industrialized countries have a major need for greater public health education and the promotion of healthy life-styles.