[Long-term study of the effect of successive surveys on tuberculosis endemia].
A whole rural population of 16359 subjects was followed for a period of 24 years. This period of 24 years is well divided from the viewpoint of the succesive systematic detection three intervals being selected, as follows: a) the stage of usual anti-tuberculous assistance; b) the stage of scientific experimentation consisting in 3 radiophotographic detections repeated every two years and the annual control of groups with high risk, between 1960--1965, completed by integral biological detection in children (every year) and bacteriological controls. The population controls were followed by the diagnosis; c) the stage of discontinuing the experiment when current antituberculous assistance was resumed, between 1966 and 1974. All cases of active pulmonary tuberculosis, that have been recorded through all the methods of investigation over a period of 24 years in all these localities are correlated, on the one hand to one another, and on the other hand with objective documents obtained during the period of intensive control of the population over the 6-years interval. Thus the limits appear more correctly, within which this natural history of the disease can be detected through various types of population control, as well as some practical consequences for the improvement of the technique and of the control methodology in the future.