In order to know the significance of placental infection by T. cruzi 820 newborn infants (NB) weighing less than or equal to 2500 grs were examined both clinically and by the Strout method and histopathological sections of the placenta in order to detect congenital infection with Chagas'disease. Thirty five (4,26%) NB presented a placentary infections by T. cruzi, but having a negative direct parasitological examination in the cord blood, these NB were followed up parasitologically (microhematocrit), in order to detec an eventual positive change in the post-partum period. The follow-up was done at 7, 15, 30 and60 days afterbirth, and with xenodiagnosis 15 days later. In 27 newborn (3.29%) it was possible to complete their follow-up with detection of T. cruzi in every case. In the control group, constituted by NB which were negative to both methods, there was no positivisation at all during the follow-up period. These observations show a high frequency of congenital T. cruzi infection in Santa Cruz.
Newborn; Placental infection; Trypanosoma cruzi; Chaga's disease Bolivia