Trypanosoma cruzi infection in Didelphis marsupialis in Santa Catarina andArvoredo Islands, southern Brazil

Between 1984 and 1993 the prevalence of the Trypanosoma cruzi infection in opossums (Didelphis marsupialis) was studied in Santa Catarina and Arvoredo Islands, State of Santa Catarina, Brazil. The association of the triatomin e bug Panstrongylus megistus with opossums nests and the infection rate of these triatomines by T, cruzi was also studied. Thirteen different location s were studied in Santa Catarina Island (SCI), in which 137 D. marsupialis were collected. Sixty two opossums were collected at the Arvoredo Island (A I), located 12 miles north from SCI. All captured animals were submitted to parasitological examinations that revealed the presence of T. cruzi in 21. 9% of the opossums captured in SCI and 45.2% among opossums captured in the AI. The presence of P. megistus was detected in most of the D. marsupialis nests collected in the SCI, however, in the non-inhabited AI only eight tr iatomines were collected during the whole study. The presence of T. cruzi-i nfected D. marsupialis associated with P. megistus in human dwellings in th e SCI, and the high infection rate of D. marsupilais by T. cruzi in the abs ence of a high vector density are discussed.