Participação dos gambás na epidemiologia da Leishmaniose na Mata Atlântica do Estado de Pernambuco, Brasil

Abstract

The occurrence of leishmaniasis has been expanding geographically in Brazil in recent years due mainly to socio-environmental changes. Due to their close association with human residences, infected marsupial species play an important role in the eco-epidemiology of leishmaniasis, especially regarding the maintenance of the parasite in the wild. The aim of the present study was to analyze the role of opossums (Didelphis sp) in metropolitan Recife and the Atlantic Forest of the state of Pernambuco, Brazil, as hosts for leishmaniasis. Blood and bone marrow samples were collected from 100 opossums from the genus Didelphis (Didelphimorphia: Didelphidae) – 74 white-eared opossum D. albiventris (36 males and 38 females) and black- eared opossum 26 D. aurita (10 males and 16 females). The animals were from seven sites of the Atlantic Forest (Estação Ecológica do Tapacurá, São Lourenço da Mata; Parque Estadual Dois Irmãos, Recife; Campo de Instrução Marechal Newton Cavalcanti, Paudalho; Parque Ecológico São José, Igarassu; Aldeia, Camaragibe; Estação Ecológica de Caetés, Abreu e Lima; and Reserva Biológica de Saltinho, Tamandaré) as well as the cities of Abreu e Lima, Camaragibe, Jaboatão dos Guararapes and Recife. The opossums were captured using Tomahawk and Sherman live traps arranged in a grid pattern on pre-existing trails. Each capture lasted six days and five nights and was carried out, on average, every two weeks, for a total catch effort of 25,231 traps/nights from January 2008 to February 2009. Blood samples were taken for the Indirect Immunofluorescence Test and a bone marrow biopsy was performed for the investigation of amastigote forms of Leishmania(L.) chagasi through a direct parasitological exam. DNA was also extracted from 29 bone marrow samples – 22 from D. albiventris (10 males and 12 females) and seven from D. aurita (1 male and 6 females). In the parasitological exam, all animals tested negative for the amastigote forms of Leishmania (L.) chagasi. The serologic exams revealed that, among the 100 opossums analyzed, only one (1%) D. albiventris (from the city of Abreu e Lima in metropolitan Recife) was positive for Leishmania (L.) chagasi and one (1%) D. aurita (from Campo de Instrução Marechal Newton Cavalcanti, Paudalho) was positive for Leishmania (L.) amazonensis. In the PCR, all opossums tested negative. Despite the low occurrence, this is the first report of Leishmania (L.) amazonensis in Didelphis aurita in the state of Pernambuco, which stresses the importance of these opossums as host for leishmaniasis in metropolitan region of Recife. Further studies are needed to clarify the role of opossums in the epidemiological chain of leishmaniasis in metropolitan Recife and the Atlantic Forest in Pernambuco, Brazil.