Congenital Chagas disease: an update

Abstract

Congenital infection with Trypanosoma cruzi is a global problem, occurring on average in 5% of children born from chronically infected mothers in endemic areas, with variations depending on the region. This presentation aims to focus on and update epidemiological data, research methods, involved factors, control strategy and possible prevention of congenital infection with T. cruzi. Considering that etiological treatment of the child is always effective if performed before one year of age, the diagnosis of infection in pregnant women and their newborns has to become the standard of care and integrated into the surveillance programs of syphilis and human immunodeficiency virus. In addition to the standard tests, polymerase chain reaction performed on blood of neonates of infected mothers one month after birth might improve the diagnosis of congenital infection. Recent data bring out that its transmission can be prevented through treatment of infected women before they become pregnant. The role of parasite genotypes and host genetic factors in parasite transmission and development of infection in foetuses/neonates has to be more investigated in order to better estimate the risk factors and impact on health of congenital infection with T. cruzi.

2 nd Brazilian Consensus on Chagas Disease, 2015

“…As discussed in the specific section on vertical transmission of T. cruzi in this Consensus, there is evidence indicating the benefit of the antiparasitic treatment, with better evolution of Chagas disease (116) (119) (120) (121) (122) , reduced risk of vertical transmission in future pregnancies (109) (116) , and lower risk of vertical transmission and evolution to spontaneous abortion by reducing the parasitemia (103) (115) .…”

“…Based on the estimated prevalence of 1% of T. cruzi infection in women between 25 and 44 years of age (17) and a risk of vertical transmission estimated as maximum of 1% for the State of Minas Gerais, it is estimated that up to 300 children were born infected that year (107) . Detection of vertical transmission is complicated in practice, since the vast majority of congenital cases is totally asymptomatic (4) (10) (102) (104) (113) (114) (115) (116) . It is a complex issue, considering the existence of little scientific evidence of population base.…”

“…The transmission may occur at any time during pregnancy, possibly being greater in the third quarter, with increasing parasitemia (116) (118) . On the other hand, the timely diagnosis of infection during pregnancy allows a more qualified care to the infected pregnant women, who should be monitored throughout gestation.…”

“…Accidental exposure to antiparasitic drug during pregnancy is not a criterion for interrupting the gestation (115) . Studies point to the possible benefit of antiparasitic treatment, with better evolution of Chagas disease (116) (119) (120) (121) (122) and reduction of the risk of vertical transmission in future gestations (109) (116) . High maternal parasitemia is associated with an increased risk of vertical transmission and abortion (103) (115) .…”

“…The risk of vertical transmission of T. cruzi depends on the level of parasitemia, maternal immune status, infecting strain and placental factors, and might occur at any stage of disease (41) (104) (113) (115) (116) .…”