Between 1999-2002, Médécins Sans Frontières-Spain implemented a project seeking to determine the efficacy and safety of benznidazole in the treatment of recent chronic Chagas disease in a cohort of seropositive children in the Yoro Department, Honduras. A total of 24,471 children were screened for Trypanosoma cruzi IgG antibodies through conventional enzyme-linked immunosorbent assays (ELISA) on filter paper. Recombinant ELISA (0.93% seroprevalence) showed 256 initially reactive cases, including 232 confirmed positive cases. Of these, 231 individuals were treated with benznidazole (7.5 mg/kg/day) for 60 days and were followed with a strict weekly medical control and follow-up protocol. At the end of the project, 229 patients were examined by the Honduras Secretariat of Health for post-treatment serological assessments; 88.2% seroconverted after 18 months and 93.9% seroconverted after three years. No differences were found in the seroconversion rates according to age or sex. Most of the side effects of the treatment were minor. These results support the argument that in areas where T. cruzi I is predominant and in areas affected by T. cruzi II, when vector transmission has been interrupted, Chagas disease diagnosis and treatment are feasible, necessary and ethically indisputable.

In nearly all of the previous multicentre studies evaluating serological tests for Trypanosoma cruzi infection, sera samples from Central or South American countries have been used preferentially. In this work we compared the reliability of the serological tests using Mexican sera samples that were evaluated in four independent laboratories. This included a reference laboratory in Brazil and three participant laboratories, including one in Central America and two in Mexico. The kappa index between Brazilian and Honduran laboratories reached 1.0 and the index for the Mexican laboratories reached 0.94. Another finding of this study was that the source of antigen did not affect the performance of the serological tests.

This study assessed public acceptance for two new vectorial control techniques for Chagas' disease: insecticidal paint and fumigant canisters. The study compared the two with traditional fenitrothion insecticide spraying. An experimental field study was performed in an endemic area of central Honduras from August to November 1992, a year after the initial application of the treatments. The objectives of the study were to determine the acceptability of the tools on the part of the population whose homes were treated, and on the part of the personnel applying the treatments. The sample size was drawn up according to a uniform protocol applied in six Latin American countries. For this study a total of 651 persons were surveyed in 15 rural communities. Along with the surveys, focus groups were used to collect information to learn the reasons for accepting or rejecting particular treatments. The survey was done with heads of households. Focus groups were done with heads of households and also with the field operators who applied the treatments. The research showed that insecticidal paint had a low level of community acceptance (28.8%). Field operators strongly disliked the paint because of problems with its transport, application, unpleasant smell, and very low effectiveness against triatomines and pest insects. The traditional insecticide was more acceptable to the community (93.9%) and to the field operators, especially for its strong effect against the triatomines and pest insects. The results showed that in order to increase the public acceptance for insecticidal paint, it would be necessary to make the paint easier to transport and apply and to increase its effectiveness. Because of their very low effectiveness, fumigant canisters did not represent an acceptable alternative for triatomine vector control. A public educational effort should be a component of any new control method developed.

Este estudio analizó la aceptación por la comunidad de dos nuevas técnicas de control de los vectores de la enfermedad de Chagas: la pintura insecticida y los botes de fumigación. Ambas fueron comparadas con la tradicional pulverización con fenitrotión. Entre agosto y noviembre de 1992, un año después de la aplicación inicial de los tratamientos, se realizó en una zona endémica del centro de Honduras un estudio experimental de campo para determinar la aceptación de las nuevas técnicas por parte de la población cuyas casas fueron tratadas y por parte del personal que aplicó los tratamientos. El tamaño de la muestra se calculó de acuerdo con un protocolo uniforme aplicado en seis países de América Latina. Se encuestaron 651 cabezas de familia de 15 comunidades rurales y se utilizaron grupos de enfoque para obtener información sobre los motivos que llevaron a los participantes a aceptar o rechazar los tratamientos utilizados; en estos grupos, además de los cabezas de familia, también participaron los trabajadores de campo que aplicaron los tratamientos. Los resultados obtenidos revelaron que la pintura insecticida tenía un bajo nivel de aceptación por la comunidad (28,2%); a los trabajadores les gustaba muy poco por los problemas relacionados con su transporte, aplicación, olor desagradable y muy baja efectividad frente a los triatominos y otros insectos. El insecticida tradicional fue más aceptable tanto para la comunidad (93,9%) como para los trabajadores, sobre todo por su potente efecto frente a los triatominos y otros insectos. Para incrementar la aceptación de la pintura insecticida sería necesario hacer más fácil su transporte y aplicación e incrementar su efectividad. Debido a su muy baja efectividad, los botes de fumigación no representaron una alternativa aceptable para el control de los triatominos. Una iniciativa de educación pública debería ser un componente de cualquier nuevo método de control que se desarrolle.

From November to December 1991 and in March 1993 a survey was conducted in 17 rural communities located in Central Honduras. The communities belonged to two areas where Chagas' disease is endemic. In one of them, disease control activities had been conducted. A total of 849 adults, one in each of an equal number of households, was interviewed. The objective of the survey was to investigate and compare in both locations knowledge about Chagas' disease and its routes of transmission, measures aimed at avoiding the presence of triatomines within households, beliefs surrounding the vector and its control, and the population's sources of information about the disease. A 23-item questionnaire was tested and precoded. Almost 100% of the subjects who were surveyed were able to identify the vector and to describe its habits, but only 30,1% knew that Triatoma is the vector for the disease and only about 6% associated it with a chronic heart condition. Around 47,9% of survey subjects indicated that eliminating triatomines from households is a personal responsibility, although 78% identified as the control measure the institutional application of insecticides. Personal contact between a health worker and community members was the chief source of information for those who mentioned having heard of Chagas' disease (41,0%). These results suggest that health education should be included as a component in the planification of control programs. The role played by triatomines in disease transmission should be emphasized, as well as the importance of carrying out household improvements, with community participation, as an effective and sustainable measure. To achieve greater impact, this component should be developed through interpersonal communication channels.

En el período de noviembre a diciembre de 1991 y en marzo de 1993 se realizó una encuesta en 17 comunidades rurales de la parte central de Honduras. Las comunidades correspondían a dos zonas en las que la enfermedad de Chagas es endémica. En una de las zonas habían tenido lugar actividades de control de la enfermedad. Fueron entrevistados 849 adultos, uno en cada uno de otros tantos hogares familiares. El objetivo de la encuesta fue investigar y comparar en ambas zonas los conocimientos sobre la enfermedad de Chagas y sus mecanismos de transmisión, las prácticas para evitar la presencia de triatómidos en las viviendas, las creencias acerca de los triatómidos y su control, y las fuentes a partir de las cuales la población obtiene información sobre la enfermedad. Se utilizó un cuestionario de 23 preguntas validado y precodificado. Casi 100% de los entrevistados pudieron reconocer el vector y conocían sus hábitos, pero solo 30,1% sabían que el Triatoma es vector transmisor de la enfermedad y apenas 6% pudieron mencionar su relación con una afección cardíaca crónica. El 47,9% de los entrevistados indicó que la responsabilidad de eliminar los triatómidos de la vivienda es personal, aunque 78% consideraron como medida de control la aplicación institucional de insecticidas. El contacto personal entre el funcionario institucional y los miembros de la comunidad fue la principal fuente de información entre los que mencionaron haber oído de la enfermedad de Chagas (41,0%). Los resultados sugieren que al planificar medidas de control se debe incluir el componente de educación sanitaria. Ha de ponerse énfasis en el papel que desempeñan los triatómidos en la transmisión, así como en la importancia de mejorar la vivienda como medida eficaz y sostenible mediante la participación de la comunidad. Este componente deberá ser desarrollado por canales de comunicación interpersonales para obtener un mayor impacto.