A comprehensive systematic review for identifying the risk factors for carrying a Trypanosoma cruzi infection in non-endemic countries

Evidence assessment

This systematic review aims to provide the evidence regarding the demographic, environmental, and epidemiological or other characteristics associated with carrying T. cruzi infection in at-risk individuals residing in areas non-endemic for CD. The characteristics associated with T. cruzi infection are referred to as risk factors in this report.

Executive summary

Background

Mass population movements have accounted for the emergence of Chagas disease (CD) outside endemic regions, including the European Union/European Economic Area (EU/EEA). The parasite responsible for causing CD, Trypanosoma cruzi, can be transmitted through substances of human origin (SoHO), such as blood transfusions and organ transplantations [1], posing a risk to the recipients. This, together with congenital transmission, is of increasing concern in non-endemic countries.

Objective

To identify which factors are consistently associated with a higher risk of carrying a Trypanosoma cruzi infection in people residing in non-endemic countries.

Methods

A comprehensive search of Medline (including PubMed) and EMBASE databases was conducted covering the period between January 2000 and June 2022 to identify observational cohort and cross-sectional studies that reported any factor associated with carrying a T. cruzi infection in non-endemic countries. Screening, data extraction, and critical appraisal (Joanna Briggs Institute tools) were undertaken by two independent study authors. Due to the heterogeneous nature of the data, vote-counting and narrative syntheses were undertaken.

Results

Thirty-three cross-sectional and 18 observational cohort studies were identified, resulting in coverage of a total population of approximately 132 million people. Synthesis highlighted the following factors as being associated with higher odds of carrying a T. cruzi infection in non-endemic countries: being born in endemic countries (Latin American countries); having stayed in endemic countries; having a history of living in rural areas of endemic countries; having a history of living in specific housing conditions in endemic countries (mud houses or those with thatched rooves); a history of blood transfusion in endemic countries; older age in people with other factors associated with T. cruzi; maternal origin from endemic countries; having a family history of CD; and generic knowledge of CD prior to testing for T. cruzi infection.

Conclusions

The assessment of the aforementioned factors will increase the ability to detect people infected with T. cruzi, supporting the eligibility assessment of SoHO donors, and implement public health measures.