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Objective: Chagas disease affects over six million people, but less than 1% are diagnosed and treated. Complicated diagnostic processes are a major barrier. Colombia’s previous diagnostic algorithm, using in-house tests, was difficult to scale up, creating significant access barriers for patients. A new algorithm using commercially manufactured immunoassays would potentially improve access, but these tests’ performance in Colombian patients with Chagas disease is not well known. Methods: We assessed seven commercially available assays. Samples (n = 501), 93.8% originating from Colombia, were characterized as positive or negative based on standard procedure at the National Reference Laboratory. Performance characteristics were calculated for individual assays and hypothetical test pairings, then compared to the existing algorithm. Results: Five of seven assays exhibited sensitivity >98% while six showed specificity >97%. A total antigen ELISA paired with a recombinant assay provided similar performance to the current diagnostic process. Six of six assays tested proved capable of detecting different Trypanosoma cruzi genetic lineages. Conclusions: The study indicated that several commercial assays accurately detect T. cruzi infection in Colombian patients. A simplified testing process with two commercial assays could perform comparably to the previous process, reducing cost and accessibility barriers and facilitating national scale-up. Keywords: Trypanosoma cruzi, Chagas disease, Enzyme-linked immunosorbent assays, Diagnostic barriers, Access to healthcare, Neglected tropical diseases (NTDs)

Colombia has one of the largest burdens of Chagas disease globally, with about 438,000 people affected according to 2015 estimates. Despite this, 1% of the population has had access to diagnosis and treatment. A patient-centered roadmap for Chagas disease was developed from 2015 onwards to address access barriers and increase diagnostic and therapeutic coverage and was implemented in five municipalities where Chagas disease is endemic. The mean number of people tested per year increased from 37 before the project to 262 following implementation, and the average days between medical order and diagnostic confirmation results decreased from 258 to 19. The mean days from diagnostic confirmation to treatment initiation decreased from 354 before the project to 135 after implementation. The 5,654 people tested included 3,467 women of childbearing age. The prevalence of T. cruzi infection was 11.5%, and thus far 266 people have received antitrypanosomal treatment. Collaborative creation and implementation of a patient-centered roadmap can address access barriers in specific contexts, helping to reduce the invisibility and burden of this neglected disease.

The Pan American Health Organization (PAHO) has defined Chagas Disease hotspots in Central America associated with the vector Triatoma spp. Triatoma dimidiata is a native vector adapted to multiple environments, including intra-domestic and peri-domestic habitats. A multi-institutional project named "Alliances for the elimination of Chagas in Central America" was created to help reduce the incidence of the disease in the region. Activities performed in the field as part of the project included aspects of vector surveillance and control, improvement of houses, diagnosis and treatment of individuals, health promotion, training of human resources and identification of access barriers to diagnosis and treatment. As a base line study, eleven villages, comprised of 1,572 households, were entomologically evaluated (83.4% overall participation); five were found to have very high infestation rates (20%), three had high infestation rates (8-20%) and three had low-infestation rates (8%), coinciding with the category of infestation-risk of the houses within each village. Serological tests were carried out in 812 people (80% participation) in two of the 11 villages and none of the 128 children tested, less than 5 years of age, were positive for Trypanosoma cruzi infection. Community participation in all the activities was high (70%). The collaboration between several subnational, national, and international institutions, each with specific roles, promoted community participation in the activities of vector control and patient care, thus, establishing a baseline to continue implementing and monitoring project progress.