Congenital Chagas Disease in the Ecuadorian Amazon: Maternal Screening at Delivery and Evaluation of Risk Factors Associated with Vector Exposure

Abstract

Congenital infection with Trypanosoma cruzi remains a major route for Chagas disease transmission in endemic and non-endemic regions. We evaluated an intervention strategy aimed to detect congenital Chagas disease cases at a major hospital in the Ecuadorian Amazon via cord blood analysis at the time of delivery. All women giving birth at the hospital during the study period (191) were invited to participate. Among them, two (1.0%) did not adjust to the inclusion criteria and four (2.1%) declined to participate in the study, showing the intervention had good acceptability among the mothers. It was possible to obtain cord blood samples during 146 of the deliveries, and only one woman was found to be seropositive, without evidence of transmission to the newborn at delivery or 8 months later. In addition, sociodemographic and economic characterization of the study population revealed that few women had previous knowledge about Chagas disease (16.1%) whereas more than half (62.5%) recognized the vector. Recognizing the vector and having seen it indoors were associated with women from rural families, involved in agriculture, and hunting in the forest. Interestingly, most women (87.3%) reported having easy access to Ecuador's national health system, suggesting serological screening during prenatal visits would be of value in this province. With a proper prenatal screening system in place, cord blood screening would allow for timely detection of T. cruzi infection in newborns from both seropositive women and the minority (2.1%) of women who do not comply with prenatal care visits.

Predictor Variables in the Spread of Chagas Disease in Rural Areas

“…The majority, 84.6%, had p < 0.05, being represented by illiteracy [76] and low education levels [53], both in the Brazilian Northeast, as well as for situations of low education levels among women found in the municipality of Pore, in Casanare, Colombia [31]. Low education levels (illiteracy to incomplete high school) are associated with the marginalization of the population and poverty [77,78], to social vulnerability [30,62,63], and to less qualified jobs [56]. It is noteworthy that congenital transmission cases in Cumural, Meta, Colombia, among which greater seroprevalence in children of mothers with below-secondary education levels have been found [67].…”

“…In Latino-American countries, considered endemic for CD, there are still places with high seroprevalence, such as in the province of Cordillera, located in the Bolivian Chaco, where seroprevalence of 22.0% in children with average age of 13 years old has been found [28]. Among many forms of CD spread in these countries, we have: vector transmission, such as in Brazil [29]; congenital transmission, such as in Ecuador [30] and Colombia [31]; oral transmission, as noticed in a Venezuelan school [32]; and by blood transfusion or organ transplant, such as in Argentina [33].…”

Phenotypic Evaluation of Nucleoside Analogues against Trypanosoma cruzi Infection: In Vitro and In Vivo Approaches

“…Due to population mobility from Latin America, CD also represents a public health issue in non-endemic areas, affecting more than six million people worldwide [3][4][5]. CD transmission involves vectorial transmission by triatomine bugs, blood transfusion, organ transplantation, vertical transmission and oral routes by the ingestion of parasite-contaminated food and drink [6][7][8]. CD displays two sequential clinical phases: the acute and the chronic phases.…”