Congenital Transmission of Trypanosoma cruzi: A Review About the Interactions Between the Parasite, the Placenta, the Maternal and the Fetal/Neonatal Immune Responses
Chagas disease (CD), caused by the protozoan parasite Trypanosoma cruzi, is
considered a neglected tropical disease by the World Health Organization. Congenital
transmission of CD is an increasingly relevant public health problem. It progressively
becomes the main transmission route over others and can occur in both endemic and
non-endemic countries. Though most congenitally infected newborns are asymptomatic
at birth, they display higher frequencies of prematurity, low birth weight, and lower
Apgar scores compared to uninfected ones, and some suffer from severe symptoms.
If not diagnosed and treated, infected newborns are at risk of developing disabling
and life-threatening chronic pathologies later in life. The success or failure of congenital
transmission depends on interactions between the parasite, the placenta, the mother,
and the fetus. We review and discuss here the current knowledge about these
parameters, including parasite virulence factors such as exovesicles, placental tropism,
potential placental defense mechanisms, the placental transcriptome of infected
women, gene polymorphism, and the maternal and fetal/neonatal immune responses,
that might modulate the risk of T. cruzi congenital transmission.This work was supported by the ERANET-LAC grants
ELAC2014/HID-0328 and ERANet17/HLH-0142 (to UK, AO,
AS, and CT), FONDECYT 1190341 (Conicyt, Chile to UK), and
PICT 2015-0074 (FONCyT, Argentina to AS)