[African towns and health: references and stakes].

Urbanization is a fairly recent phenomenon. Thus during the 19th century, only 5% of the population was living in town. However it is more and more important as urban population has been multiplied by 15 since 1900. In Africa, this evolution is still more recent and the continent remains poorly urbanized. But the rate of urbanization is the fastest in the world and demographic forecasts indicate that by 2025, more than 50% of the African population will live in towns. Consequences of urbanization on human development are not well known. Concepts of demographic and epidemiological transitions were widely used for health. Health transition is another concept, including cultural, social and behavioural determining factors as well as ways of caring and being cared for. These processes account for the reduction of infectious diseases through a fall of mortality and birth rates and the emergence of non-transmissible diseases like cardiovascular diseases, cancers, mental diseases.... Although health situation is depicted as better in towns (better immunization, health care offer, better access to health care...), mortality and morbidity patterns seem to change more quickly in towns than in rural areas. However this is not true everywhere in urban areas where several towns are to be found within the same town and for example, health of populations living on margins may be worse than that of rural populations. Urban people resort to modern health care together with traditional healers, even informal, sometimes illegal health care, involving heavy costs but offering no guarantee as regards their quality and their efficiency for patients and society. It appears that developing countries have to face a new health care demand quite different from the one they used to face before, when they have simultaneously to cope with uncontrolled town growth. Under these conditions, urban health should become a priority.