Resumen

MORENO, Elio A et al. Research on vertical transmission of Trypanosoma cruzi in chronically infected Wistar rats.. Bol Mal Salud Amb [online]. 2006, vol.46, n.2, pp.149-160. ISSN 1690-4648.

We give the results of an experimental study on possible vertical transmission of Trypanosoma cruzi in chronically infected Wistar rats. The progress of the infection was evaluated before, during and after parturition with parasitological, serological and histopathological tests. Infected virgin rats and healthy gestating rats were used as control. Direct parasitological examinations of blood samples, blood cultures and xenodiagnosis carried out on mothers and offspring did not reveal patent or sub-patent parasitemias. At the same time, serological tests with IIF and ELISA on virgin rats (A) and infected gestating rats (B) and offspring showed specific anti- T. cruzi antibodies in 100 % of infected mothers and 26.2 and 44.6 % of offspring, while the figures for healthy offspring nursing from infected mothers was 41.6 and 83.3 %. Histopathological tests showed slight parasitic persistence in cardiac, skeletal muscle and in stroma from a placenta; discrete myocarditis and myositis with features of chronicity; moderate inflammatory infiltrate without parasitism in the uterus, umbilical cord and mammary glands. These results suggest that fetal infection is possible in Wistar rats with chronic chagasic infection. There follows a discussion of the factors that might produce the variations noted in congenital T. cruzi transmission, including the pathogenicity of the strain, the parasite forms used and the amount inoculated.

Palabras clave : Trypanosoma cruzi; vertical transmission; Wistar rat; chronic infection.