Epidemiological surveillance of infectious diseases in France

Epidemiological surveillance, namely the continuous monitoring of diseases and health determinants in a population, has developed over the past fiftee n years, in the sphere of human health as well as in animal health. All epi demiological surveillance networks include the following four stages: data collection, data transmission, data processing and dissemination of informa tion. However, despite this basic similarity, the very many networks existi ng in France are extremely varied in nature. At the national level, the bod ies involved in epidemiological surveillance for infectious animal diseases are the Direction generale de l'alimentation, the Agence francaise de se'c urite' sanitaire des aliments and, to a lesser degree, the Institut francai s de recherche pour l'exploitation de la mer. In the field, the networks re ly on the Direction des services veterinaires, veterinary practitioners, la boratories in each department, and livestock producers' groups (especially animal health protection groups). Some twenty French networks currently in operation are presented in this article according to a classification based on published criteria. In the case of human infectious diseases, epidemiol ogical surveillance is carried out almost entirely by the Direction general e de la sante' and the Directions departementales d'action sanitaire et soc iale, the Institut de veille sanitaire and the various Centres nationaux de reference (CNRs). Most human infectious diseases are monitored by one or m ore of the following broad categories of networks: reporting of notifiable diseases, the CNRs, the network of sentinel doctors, the network of hospita l laboratories and departments, and medical causes of death. An example whe re surveillance is covered by several networks is also presented, namely su rveillance for salmonellosis and Salmonella. Lastly, methods for evaluating networks are discussed.