[Sampling surveys: an objective method of evaluating the prevalence of leprosy in an endemic zone].

The authors submit a simplified sample survey methodology designed to evaluate prevalence rates of leprosy. The system proposed uses a cluster sampling technique. A cluster is a randomly selected group of households. In each household visited by the epidemiological teams all the inhabitants of the target-group are interviewed and examined. Various samples sizes are used (from 6500 to 12,000 peoples) according to the expected prevalence rate of the studied area. All the new cases detected through these surveys are notified to the National Departments in charge of leprosy programmes. Two surveys are already achieved (Equatorial Guinea, Cameroon), a third one in on the way.