Tropical diseases: the burden and its implications.

The weight of disease in developing countries may be viewed as a burden, but it also provides opportunities and challenges in research, practical and altruistic action and ecological understanding. Of the classical parasitic diseases, 10 are to be found in the top 100 major diseases in the world. The burden of tropical diseases is much greater in Africa, with far fewer resources available. Infectious diseases are combined with diseases of poverty. High fertility, slow economic growth, deforestation, rapid urbanization and increased migration contribute to the recent changes in transmission and distribution of diseases observed in developing countries. The burden of diseases in tropical and developing countries remains massive. New, especially molecular, parasitological techniques and lines of research, and scientific methods for investigations and management of tropical diseases can contribute to the reduction of the burden of disease while providing a better understanding of parasites and their interactions with their hosts.