Feasibility, Drug Safety, and Effectiveness of Etiological Treatment Programs for Chagas Disease in Honduras, Guatemala, and Bolivia: 10-Year Experience of Médecins Sans Frontières

Abstract

BackgroundChagas disease (American trypanosomiasis) is a zoonotic or anthropozoonotic disease caused by the parasite Trypanosoma cruzi. Predominantly affecting populations in poor areas of Latin America, medical care for this neglected disease is often lacking. Médecins Sans Frontières/Doctors Without Borders (MSF) has provided diagnostic and treatment services for Chagas disease since 1999. This report describes 10 years of field experience in four MSF programs in Honduras, Guatemala, and Bolivia, focusing on feasibility protocols, safety of drug therapy, and treatment effectiveness.MethodologyFrom 1999 to 2008, MSF provided free diagnosis, etiological treatment, and follow-up care for patients <18 years of age seropositive for T. cruzi in Yoro, Honduras (1999–2002); Olopa, Guatemala (2003–2006); Entre Ríos, Bolivia (2002–2006); and Sucre, Bolivia (2005–2008). Essential program components guaranteeing feasibility of implementation were information, education, and communication (IEC) at the community and family level; vector control; health staff training; screening and diagnosis; treatment and compliance, including family-based strategies for early detection of adverse events; and logistics. Chagas disease diagnosis was confirmed by testing blood samples using two different diagnostic tests. T. cruzi-positive patients were treated with benznidazole as first-line treatment, with appropriate counseling, consent, and active participation from parents or guardians for daily administration of the drug, early detection of adverse events, and treatment withdrawal, when necessary. Weekly follow-up was conducted, with adverse events recorded to assess drug safety. Evaluations of serological conversion were carried out to measure treatment effectiveness. Vector control, entomological surveillance, and health education activities were carried out in all projects with close interaction with national and regional programs.ResultsTotal numbers of children and adolescents tested for T. cruzi in Yoro, Olopa, Entre Ríos, and Sucre were 24,471, 8,927, 7,613, and 19,400, respectively. Of these, 232 (0.9%), 124 (1.4%), 1,475 (19.4%), and 1,145 (5.9%) patients, respectively, were diagnosed as seropositive. Patients were treated with benznidazole, and early findings of seroconversion varied widely between the Central and South American programs: 87.1% and 58.1% at 18 months post-treatment in Yoro and Olopa, respectively; 5.4% by up to 60 months in Entre Ríos; and 0% at an average of 18 months in Sucre. Benznidazole-related adverse events were observed in 50.2% and 50.8% of all patients treated in Yoro and Olopa, respectively, and 25.6% and 37.9% of patients in Entre Ríos and Sucre, respectively. Most adverse events were mild and manageable. No deaths occurred in the treatment population.ConclusionsThese results demonstrate the feasibility of implementing Chagas disease diagnosis and treatment programs in resource-limited settings, including remote rural areas, while addressing the limitations associated with drug-related adverse even...

High seroconversion rates in Trypanosoma cruzi chronic infection treated with benznidazole in people under 16 years in Guatemala

“…Despite the limiting circumstances, the fi ndings from this study are consistent with previously documented initiatives in the region (3) (4) (13) . The closest and more comparable results correspond to those published on a cohort of 231 Honduran children treated with BZN in 2009; whereby 93.9% seroconverted (negative serological results) 36 months after antiparasitic treatment (3) .…”

“…One of the main barriers for the widespread use of BZN is the high reported incidence of adverse drug reactions (ADRs), documented in up to 50% of treated patients (11) . Whereas only a minor number of ADRs are severe (1%) (12) , about a third of patients interrupt BZN treatment due to ADRs or other reasons (11) (12) (13) .…”

“…As mentioned by Yun et al (13) , the success of MSF projects derived mostly from weekly assessment of patients during treatment. This increased adherence enabled the early detection of any adverse reaction, reduced the proportion of moderate and severe reactions, and maintained a 0% mortality rate.…”

“…At a clinical level, previous studies have demonstrated for example that digestive forms are rare north of the Equator and that chagasic heart disease becomes more severe and evident in the central regions of South America compared to endemic areas in the south (5) (16) or even in Central America. In terms of therapeutic response and when compared to fi ndings from studies conducted in Bolivia (13) , patients from Central America require a shorter follow-up time after treatment to ascertain cure or detect a reduction in T. cruzi antibodies.…”

Non, la maladie de Chagas n’est pas le nouveau sida des Amériques !

“…C'est une des raisons pour laquelle les décideurs des pays endémiques continuent de privilégier la lutte antivectorielle ainsi que la prévention de tous les autres modes de transmission, et se montrent réservés vis-à-vis d'un traitement qui a beaucoup de mal à faire ses preuves et concernerait les neuf à dix millions de chagasiques chroniques que compte encore le souscontinent latino-américain. Par contre, il existe aujourd'hui une manière de consensus pour traiter tous les séropositifs âgés de moins de 18 ans, avec des résultats qui sont extrê-mement variables d'une région à l'autre [38]. Seule la mise au point d'un test permettant, dans un délai raisonnable, d'affirmer la guérison serait susceptible de faire bouger les lignes dans ce domaine.…”