A retrospective analysis was carried out on census data collected from house-to-house surveys during 19911992 in 4 areas endemic for Andean cutaneous leishmaniasis (uta) in the Department of Lima, Peru. Major changes in mean annual incidence in susceptible persons have taken place in these sites during the last 60 years. In particular, there is strong support for the hypothesis that, from the 1950s to the 1970s, the transmission rate was temporarily suppressed, largely as a by-product of the DDT house spraying campaign against malaria. These results are consistent with (i) anecdotal evidence, contemporary with the spraying campaign, and (ii) the official Ministry of Health records for the annual number of uta cases in the Departments of Lima and Ancash. © 1994 Oxford University Press.