[Tegumentary leishmaniasis in area with epidemic levels of transmission, Salta, Argentina, 1998].

The incidence of tegumentary leishmaniasis increased in October 1997, in an area close to Oran city, province of Salta. The leishmaniasis' epidemiology and the entomology of this outbreak were studied during June 1998 at Paraje Las Carmelitas and Río Blanco, places with high reported incidence. The prevalence of infection (Montenegro Skin Test reactive) was 171/1000 inhabitants in Paraje Las Carmelitas and 790/1000 in Río Blanco, while the rates of leishmaniasis' incidence (active ulcers) were 72/1000 and 790/1000. The prevalence differences among sex and age groups were not significant. The clinical and epidemiologic patterns were consistent with those reported in the area for Leishmania (Viannia) braziliensis. Lutzomyia intermedia was the prevalent species (96%) among 2577 Phlebotominae collected, Lu. shannoni, Lu. cortelezzii y Lu. migonei were also present. The results about distribution of prevalence by age, and spatial distribution of Phlebotominae supported deforestation-residual primary forest transmission hypotheses. Therefore, in Salta the epidemic outbreaks generated by extensive deforestation could be sustained and amplified because the human settlements are located close to the remaining primary forest "spots". Furthermore, in this scenario the risk of human-vector contact increases by the subsistence or recreational activities performed in secondary transitional forests, and the presence of domestic animals around the houses. The results are discussed in the frame of possible control strategies.