Discussion

Following successful Chagas disease control programs across Latin America, congenital Trypanosoma cruzi transmission has become proportionally more important, accounting for 22% of new infections. Treatment during infancy is more efficacious and better tolerated than later, but current diagnostic methods fail to detect >50% of infected neonates and <20% complete follow-up. Pregnant women presenting for delivery in two urban hospitals in Santa Cruz, Bolivia, were recruited and their infants monitored at 1, 3, 6 and 9 months after birth to evaluate the performance of qPCR, IgM Western blots and micromethod for congenital Chagas disease screening. Of 518 infants from 507 seropositive women, unequivocal congenital transmission was identified in 32 infants of 29 mothers, including 3 sets of twins (5.7% transmission rate). Vertical transmission was more likely to occur in younger (23.5 vs. 26.9 years), first time mothers (7 vs. 52 mothers). Congenital T. cruzi infection was significantly associated with severe clinical outcomes including, premature birth and low birth weight and uninfected infants born to seropositive mothers were more likely to suffer from respiratory distress and premature rupture of the amniotic sac. We critically discuss the technical, logistical and economic obstacles of implementing routine molecular screening for congenital Chagas disease in resource-limited settings and describe the future prospects for improved disease management.