| Abstract: | Trypanosoma cruzi strains from distinct geographic areas show differences in drugresistance and association between parasites genetic and treatment response has beenobserved. Considering that benznidazole (BZ) can reduce the parasite burden andtissues damage, even in not cured animals and individuals, the goal is to assess thedrug response to BZ of T. cruzi II strains isolated from children of theJequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infectedand treated with BZ in both phases of infection were compared with the untreated andevaluated by fresh blood examination, haemoculture, polymerase chain reaction,conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated inthe acute phase, a significant decrease in parasitaemia was observed for all strains.Positive parasitological and/or serological tests in animals treated during the acuteand chronic (95.1-100%) phases showed that most of the strains were BZ resistant.However, beneficial effect was demonstrated because significant reduction (p <0.05%) and/or suppression of parasitaemia was observed in mice infected with allstrains (acute phase), associated to reduction/elimination of inflammation andfibrosis for two/eight strains. BZ offered some benefit, even in not cured animals,what suggest that BZ use may be recommended at least for recent chronic infection ofthe studied region. |
