Epidemiology and tropical public health: current and future contributions with particular emphasis on the role of the London School of Hygiene and Tropical Medicine.

This paper presents a forward look at the contribution of epidemiology to public health in developing countries and pays particular attention to the present and future role of the London School of Hygiene and Tropical Medicine. Three types of epidemiology are distinguished for the purposes of the paper: micro-epidemiology, desk epidemiology and macro-epidemiology. Micro-epidemiology, the application of epidemiology to particular health problems in particular settings, is illustrated through examples in both child and adult health. More emphasis on acute respiratory infections in children, maternal and neonatal health, and adult health in general is advocated. The contributions of desk epidemiology are illustrated through examples of the exploration of the effects of confounding and mis-classification. Continued attention to theoretical and methodological issues is essential if the quality and cost-effectiveness of field studies are to continue to improve. Macro-epidemiology is concerned with the absolute and relative contributions of particular causes or diseases to the overall burden of ill-health in a population. It is a young field in which important advances may be made in the 1990s. Its results are highly relevant to policy making and resource allocation in the health sector. In conclusion, the relationship between epidemiologists in developed and developing countries is briefly discussed and some recommendations are made.