Congenital infection with Trypanosoma cruzi: from mechanisms of transmission to strategies for diagnosis and control.

The transmission rate of congenital T. cruzi infection (number of congenital cases/number of chagasic mothers) in the Southern Cone countries varies widely, from 1% in Brazil to 4 to 12% Argentina, Bolivia, Chile and Paraguay. These differences were discussed at length, and attributed to the different methodologies used for detection of congenital cases, and/or possible special characteristics from the infecting parasites, differences in the immunological, genetical or nutritional status of the mother, or specific epidemiological situations remaining to be studied.