Epidemiology of the American cutaneous leishmaniasis in a military training center in "Zona da Mata", Pernambuco, Brazil

Abstract

The objective of this study was to characterize aspects of the ecoepidemiology of the American cutaneous leishmaniasis (ACL) caused by Leishmania (Viannia) braziliensis in an area of military training located in the Atlantic rain forest (“Zona da Mata”) region in the Pernambuco State, Brazil, to isolate and identify Leishmania species in patients and sand fly fauna, the expression of infection and disease and vector(s) involved in the transmission. Sand flies were captured between July 2002 and June 2003 in the places where diurnal and nocturnal training activities were realized. Patients were reported to the “Hospital Geral do Exercito”, in Recife, for clinical diagnostic and treatment. Laboratory diagnosis was confirmed by parasite demonstration and detection of immune response to Leishmania. An epidemiological survey by Montenegro skin test (MST) was carried out to identify the prevalence of infection in the population that made training activities in this area. Nine ACL cases were notified during the study period, eight of them from patients with single cutaneous lesions and one from a patient with multiple lesions. A total of 370 individuals were submitted to MST, and 89 presented positive response, representing 25.28% of prevalence to infection. Six Leishmania (Viannia) braziliensis stocks were isolated from patients and one from a sentinel hamster exposed in the area, characterized by monoclonal antibodies and isoenzymatic profiles. A total of 8,406 sand flies specimens of sixteen species were collected and identified. Lutzomyia (Psychodopygus) complexa was the predominant species, with 51.36% of the total, followed by L. choti, L. amazonensis, L. longispina and L. sordelli. One isolation of flagellated form characteristic of Leishmania was obtained from L. complexa, but not identified due to culture contamination. These results support evidences of the enzootic cycle maintenance involved in this area, with periodical ACL outbreaks after training activities carried out in places of local remnant forests where occurs the primary transmission cycle of L. (V.) braziliensis in this area.