Propuestas para mejorar la vivienda rural en zonas afectadas por el mal de chagas : Santiago del Estero, Argentina

Este trabajo presenta resultados de la investigación sobre el mejoramiento de la vivienda tradicional de zonas afectadas por el Mal de Chagas, en el Noreste de Santiago del Estero. Se refieren al monitoreo técnico de cielorrasos y revoques de suelo-cemento y al diseño de un módulo básico mejorado para vivienda. La arquitectura propuesta se basa en el uso de recursos locales, especialmente la tierra cruda estabilizada, combinada con estructura de madera. La investigación es interdisciplinaria, con participación de la comunidad beneficiaría. Surgió como un proyecto de cooperación entre la Universidad de Buenos Aires y la Dirección Nacional de Epidemiología del Ministerio de Salud y Acción Social de la Nación.This paper describes the results of a project focused in the improvement of the traditional earth dwelling in an infested rural village of the Northeast of Santiago del Estero, Argentina, in Chagas’ desease areas. Work is now developing ceilings and plasters and a new house basic module. Proposals privilegiates lowcost solutions based in the use of local resources, stabilized earth components and wooden frame. Methodology includes interdisciplinary work, local people participation and field prototypes. Project begun in the University of Buenos Aires in cooperation with the Epidemiology National Direction of the National Health and Social Action Ministery.Facultad de Arquitectura y Urbanism

Propuestas para mejorar la vivienda rural en zonas afectadas por el mal de chagas : Santiago del Estero, Argentina

Este trabajo presenta resultados de la investigación sobre el mejoramiento de la vivienda tradicional de zonas afectadas por el Mal de Chagas, en el Noreste de Santiago del Estero. Se refieren al monitoreo técnico de cielorrasos y revoques de suelo-cemento y al diseño de un módulo básico mejorado para vivienda. La arquitectura propuesta se basa en el uso de recursos locales, especialmente la tierra cruda estabilizada, combinada con estructura de madera. La investigación es interdisciplinaria, con participación de la comunidad beneficiaría. Surgió como un proyecto de cooperación entre la Universidad de Buenos Aires y la Dirección Nacional de Epidemiología del Ministerio de Salud y Acción Social de la Nación.This paper describes the results of a project focused in the improvement of the traditional earth dwelling in an infested rural village of the Northeast of Santiago del Estero, Argentina, in Chagas’ desease areas. Work is now developing ceilings and plasters and a new house basic module. Proposals privilegiates lowcost solutions based in the use of local resources, stabilized earth components and wooden frame. Methodology includes interdisciplinary work, local people participation and field prototypes. Project begun in the University of Buenos Aires in cooperation with the Epidemiology National Direction of the National Health and Social Action Ministery.Facultad de Arquitectura y Urbanism

Propuestas para mejorar la vivienda rural en zonas afectadas por el mal de chagas : Santiago del Estero, Argentina

Este trabajo presenta resultados de la investigación sobre el mejoramiento de la vivienda tradicional de zonas afectadas por el Mal de Chagas, en el Noreste de Santiago del Estero. Se refieren al monitoreo técnico de cielorrasos y revoques de suelo-cemento y al diseño de un módulo básico mejorado para vivienda. La arquitectura propuesta se basa en el uso de recursos locales, especialmente la tierra cruda estabilizada, combinada con estructura de madera. La investigación es interdisciplinaria, con participación de la comunidad beneficiaría. Surgió como un proyecto de cooperación entre la Universidad de Buenos Aires y la Dirección Nacional de Epidemiología del Ministerio de Salud y Acción Social de la Nación.This paper describes the results of a project focused in the improvement of the traditional earth dwelling in an infested rural village of the Northeast of Santiago del Estero, Argentina, in Chagas’ desease areas. Work is now developing ceilings and plasters and a new house basic module. Proposals privilegiates lowcost solutions based in the use of local resources, stabilized earth components and wooden frame. Methodology includes interdisciplinary work, local people participation and field prototypes. Project begun in the University of Buenos Aires in cooperation with the Epidemiology National Direction of the National Health and Social Action Ministery.Facultad de Arquitectura y Urbanism

Where do these bugs come from? Phenotypic structure ofTriatoma infestans populations after control interventions in the Argentine Chaco

House re-invasion by native triatomines after insecticide-based control campaigns represents a major threat for Chagas disease vector control. We conducted a longitudinal intervention study in a rural section (Area III, 407 houses) of Pampa del Indio, northeastern Argentina, and used wing geometric morphometry to compare pre-spray and post-spray (re-infestant bugs) Triatoma infestanspopulations. The community-wide spraying with pyrethroids reduced the prevalence of house infestation by T. infestans from 31.9% to < 1% during a four-year follow-up, unlike our previous studies in the neighbouring Area I. Two groups of bug collection sites differing in wing shape variables before interventions (including 221 adults from 11 domiciles) were used as a reference for assigning 44 post-spray adults. Wing shape variables from post-spray, high-density bug colonies and pre-spray groups were significantly different, suggesting that re-infestant insects had an external origin. Insects from one house differed strongly in wing shape variables from all other specimens. A further comparison between insects from both areas supported the existence of independent re-infestation processes within the same district. These results point to local heterogeneities in house re-infestation dynamics and emphasise the need to expand the geographic coverage of vector surveillance and control operations to the affected region

A motorized vehicle-mounted sprayer as a new tool for Chagas disease vector control

Abstract: Residual insecticide spraying still is the main tool used to suppress house infestations with Chagas disease vectors. While manual compression sprayers (MCS) have traditionally been used in Latin America, Mendoza's vector control program from Argentina introduced the use of a modified motorized vehicle-mounted sprayer (VMS) with apparent advantages over MCS. We conducted a randomized intervention trial to evaluate the effectiveness and selected components of the performance of MCS and VMS. We assessed house infestation by Triatoma infestans in 76 previously-infested houses at 0, 1, 4 and 12 months postintervention. Infestations were reduced substantially, with no significant differences between treatments. End-point infestations were restricted to peridomiciles. Although VMS required less time to complete the house spraying than MCS, both treatments had similar performance and did not suppress infestations completely. The main relative advantages of VMS were a reduced physical effort, especially under harsh field conditions, and potential gains in spray coverage per unit of time

A motorized vehicle-mounted sprayer as a new tool for Chagas disease vector control

Abstract: Residual insecticide spraying still is the main tool used to suppress house infestations with Chagas disease vectors. While manual compression sprayers (MCS) have traditionally been used in Latin America, Mendoza's vector control program from Argentina introduced the use of a modified motorized vehicle-mounted sprayer (VMS) with apparent advantages over MCS. We conducted a randomized intervention trial to evaluate the effectiveness and selected components of the performance of MCS and VMS. We assessed house infestation by Triatoma infestans in 76 previously-infested houses at 0, 1, 4 and 12 months postintervention. Infestations were reduced substantially, with no significant differences between treatments. End-point infestations were restricted to peridomiciles. Although VMS required less time to complete the house spraying than MCS, both treatments had similar performance and did not suppress infestations completely. The main relative advantages of VMS were a reduced physical effort, especially under harsh field conditions, and potential gains in spray coverage per unit of time

High levels of human infection with Trypanosoma cruzi associated with the domestic density of infected vectors and hosts in a rural area of northeastern Argentina

Abstract Background Insecticide spraying campaigns designed to suppress the principal vectors of the Chagas disease usually lack an active surveillance system that copes with house reinvasion. Following an insecticide campaign with no subsequent surveillance over a 12-year period, we implemented a longitudinal intervention programme including periodic surveys for Triatoma infestans, full-coverage house spraying with insecticides, and selective control in a well-defined rural area of the Argentinean Chaco inhabited by Creoles and one indigenous group (Qom). Here, we conducted a cross-sectional study and report the age-specific seroprevalence of human T. cruzi infection by group, and examine the association between human infection, the onset of the intervention, the relative density of infected domestic bugs, and the household number of infected people, dogs, or cats. Results The seroprevalence of infection among 691 residents examined was 39.8% and increased steadily with age, reaching 53–70% in those older than 20 years. The mean annual force of infection was 2.5 per 100 person-years (95% CI: 1.8–3.3%). Infection in children younger than 16 years born before the intervention programme was two to four times higher in houses with infected T. infestans than in houses without them and was six times higher when there were both infected dogs or cats and bugs than when they were absent. The model-averaged estimate of the intervention effect suggests that the odds of seropositivity were about nine times smaller for those born after the onset of the intervention than for those born before it, regardless of ethnic background, age, gender, household wealth, and cohabitation with T. cruzi-infected vectors or human hosts. Human infection was also closely associated with the baseline abundance of infected domestic triatomines and the number of infected cohabitants. Two of 43 children born after interventions were T. cruzi-seropositive; since their mothers were seropositive and both resided in apparently uninfested houses they were attributed to vertical transmission. Alternatively, these cases could be due to non-local vector-borne transmission. Conclusions Our study reveals high levels of human infection with T. cruzi in the Argentinean Chaco, and the immediate impact of sustained vector surveillance and selective control actions on transmission