The study of a measles epidemic in the Ribeirão Preto region, in 1984, showed a high proportion of cases occurring among people above 15 years of age. This finding led to the identification of a particular characteristic of the disease's distribution in the area, i.e. the high incidence among rural workers (especially those restricted to collective lodgings when working in agricultural and industrial activities related to sugar cane plantations). A methodological exercise of synthesis between the descriptive phase of the traditional epidemiology and the was carried out. This procedure aimed at incorporating some aspects of the social process of the area with a view to explaining this particular distribution of measles as a result to that social process (i.e. the pattern of the occurrence of measles among rural workers is understood as a historically determined social event). Finally, the need to consider the appearance of specific diseases in different human groups according to the social process into which they are inserted in disenssed in such a way that their history and specificity are taken into account.