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

Triatoma brasiliensis Neiva, 1911: food sources and diversity of Trypanosoma cruzi in wild and artificial environments of the semiarid region of Ceará, northeastern Brazil

Abstract Background Knowledge of triatomine food sources in different ecotopes enables the estimation of T. cruzi transmission risk in diverse environments, as well as its dynamics of dispersion and ecological niche. For Triatoma brasiliensis in the Caatinga, in the northeast of Brazil, seasonal differences influence feeding eclecticism and rates of T. cruzi infection. The objective of the present study was to monitor food sources and to characterize the populations of T. cruzi associated with T. brasiliensis in wild and domestic environments in the Caatinga of northeast Brazil. Methods A cross-sectional study based on a search for triatomines in wild and domestic environments, was undertaken at five different time periods from 2009 to 2015. Insects from 2015 were used for identification of food sources. Two universal primers, based on the conserved regions of the 12S rRNA locus, were used to amplify fragments of 215 bp. The content of the intestinal tract of triatomines was identified by a comparison between the sequences obtained and those deposited in the GenBank database, using BLAST. In triatomines with parasitological diagnosis of infection by trypanosomatids, xenoculture was performed for the isolation and characterization of strains, using cox2, the amplification of the SL-IL mini-exon intergenic spacer and the polymorphism of the D7 divergent domain of the gene 24αrDNA-LSU. Results Food sources were identified in 76.3% (213/279) T. brasiliensis specimens sampled in 2015. The most frequent sources in a total of 20 vertebrate species were: rodents (58%, 123/213), ruminants (30%, 64/213) and cats (6%, 12/213). A total of 49% (44/89) of the samples of T. cruzi isolated in the period from 2009 to 2015 were characterized: TcII (43%, 19/44), TcI (41%, 18/44) and TcIII (16%, 7/44). Conclusions The feeding eclecticism of T. brasiliensis shows its importance in maintaining the transmission dynamics of T. cruzi, with evidence of intense circulation between anthropic and wild environments. Attention should be placed on the association among T. brasiliensis, rodents and ruminants, in addition to the presence of TcIII in the study region