Trypanosoma cruzi infection in Latin American pregnant women living outside endemic countries and frequency of congenital transmission: a systematic review and meta-analysis

Background: Chagas disease, as a consequence of globalization and immigration, is no more restricted to Central and Latin America. Therefore, congenital transmission represents a growing public health concern in non-endemic countries.

Methods: The aim of this study was to assess the prevalence of Trypanosoma cruzi infection in pregnant Latin American (LA) women living outside endemic countries and the rate of congenital transmission. Data were extracted from studies indexed in PubMed, Scopus, Embase, Lilacs and SciELO databases without language restriction. Two investigators independently collected data on study characteristics, diagnosis, prevalence of infection in pregnant women and congenital infection rate. The data were pooled using a random effects model.

Results: The search identified 1078 articles of which 29 were eligible regarding prevalence of T. cruzi infection among pregnant women and 1795 articles of which 32 were eligible regarding the congenital transmission rate. The estimated pooled prevalence of T. cruzi infection in LA pregnant women was 4.2% [95% confidence interval (CI): 3.0-5.5]. The prevalence of T. cruzi infection in pregnant women from Bolivia was 15.5% (95% CI: 11.7-19.7) and 0.5% (95% CI: 0.2-0.89) for those coming from all other LA countries. The estimated global rate of congenital transmission was 3.5% (95% CI: 2.5-4.5); excluding poor-quality studies, the rate of congenital transmission was 3.8% (95% CI: 2.4-5.1).

Conclusions: Prevalence of Chagas disease among LA pregnant women living outside endemic countries is high, particularly in Bolivian women. The rate of vertical transmission of T. cruzi infection is similar to the rate reported in South and Central American countries.