Infección por Enfermedad de Chagas, sífilis, brucelosis y TBC en trabajadores rurales del Partido de General Pueyrredón

Fil: Vacchino, Marta Noemí. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Epidemiología Dr. Juan H. Jara; Argentina.Fil: Spillmann, Cynthia. Coordinación Nacional de Control de Vectores; ArgentinaFil: Lavalle, S.Determinar la prevalencia de infección chagásica, para sífilis y brucelosis, prevalencia de cicatriz BCG y otras variables epidemiológicas en una población de trabajadores de las áreas rurales de Mar del Plata concurrentes al Laboratorio de INE "Dr. Juan H. Jara" en los meses febrero y marzo de 1993. A cada participante se le realizó una encuesta epidemiológica y la extracción de una muestra de sangre. Se efectuó reacción de Hemoaglutinación Indirecta (H.A.I.) y test de Inmunofluorescencia para Chagas (T.I.F.); V.D.R.L. y Microhemoaglutinación para Sífilis y test de Huddleson para Brucelosis. Se aplicó intradermoreacción P.P.D. y efectuó su lectura a las 72 hs. Resultados : se encuestaron 342 personas con edades comprendidas entre 14 y 65 años, el 89,2 por ciento de sexo masculino y 10,8 por ciento de sexo femenino. El 32 por ciento provenían de Bolivia, 30 por ciento de Santiago del Estero y el resto de otras provincias y países limítrofes. El 54 por ciento no asistió o lo hizo incompletamente a la escuela primaria, mostrando las mujeres mayor deterioro de su escolaridad. El 61,7 por ciento de los encuestados tiene intenciones de radicarse en la Pcia. de Buenos Aires (de estos, la tercera parte declaró ya estar redicado). El 40,2 por ciento de la población estudiada presentó infección por Tripanosoma cruzi. Se observó incremento de riesgo con la edad, lugar de nacimiento y menor escolaridad (estratificada por edad). No se observó diferencia estadísticamente significativa entre sexos. La tasa de positividad general para sífilis fue de 2,4 por ciento . A pesar de observarse factores de riesgo para brucelosis, la tasa de prevalencia fue cero. Sobre 265 encuestados, el 69,4 por ciento presentó una o más cicatrices BCG y el 23 por ciento reacción a P.P.D. con un halo de 10 o más mm. No hubo asociación entre presencia de cicatriz BCG y respuesta P.P.D. Conclusión : la alta prevalencia de infección chagásica enfatiza la necesidad de mantene

Infección por Enfermedad de Chagas, sífilis, brucelosis y TBC en trabajadores rurales del Partido de General Pueyrredón

Fil: Vacchino, Marta Noemí. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Epidemiología Dr. Juan H. Jara; Argentina.Fil: Spillmann, Cynthia. Coordinación Nacional de Control de Vectores; ArgentinaFil: Lavalle, S.Determinar la prevalencia de infección chagásica, para sífilis y brucelosis, prevalencia de cicatriz BCG y otras variables epidemiológicas en una población de trabajadores de las áreas rurales de Mar del Plata concurrentes al Laboratorio de INE "Dr. Juan H. Jara" en los meses febrero y marzo de 1993. A cada participante se le realizó una encuesta epidemiológica y la extracción de una muestra de sangre. Se efectuó reacción de Hemoaglutinación Indirecta (H.A.I.) y test de Inmunofluorescencia para Chagas (T.I.F.); V.D.R.L. y Microhemoaglutinación para Sífilis y test de Huddleson para Brucelosis. Se aplicó intradermoreacción P.P.D. y efectuó su lectura a las 72 hs. Resultados : se encuestaron 342 personas con edades comprendidas entre 14 y 65 años, el 89,2 por ciento de sexo masculino y 10,8 por ciento de sexo femenino. El 32 por ciento provenían de Bolivia, 30 por ciento de Santiago del Estero y el resto de otras provincias y países limítrofes. El 54 por ciento no asistió o lo hizo incompletamente a la escuela primaria, mostrando las mujeres mayor deterioro de su escolaridad. El 61,7 por ciento de los encuestados tiene intenciones de radicarse en la Pcia. de Buenos Aires (de estos, la tercera parte declaró ya estar redicado). El 40,2 por ciento de la población estudiada presentó infección por Tripanosoma cruzi. Se observó incremento de riesgo con la edad, lugar de nacimiento y menor escolaridad (estratificada por edad). No se observó diferencia estadísticamente significativa entre sexos. La tasa de positividad general para sífilis fue de 2,4 por ciento . A pesar de observarse factores de riesgo para brucelosis, la tasa de prevalencia fue cero. Sobre 265 encuestados, el 69,4 por ciento presentó una o más cicatrices BCG y el 23 por ciento reacción a P.P.D. con un halo de 10 o más mm. No hubo asociación entre presencia de cicatriz BCG y respuesta P.P.D. Conclusión : la alta prevalencia de infección chagásica enfatiza la necesidad de mantene

Spatial Heterogeneity and Risk Maps of Community Infestation by Triatoma infestans in Rural Northwestern Argentina

Background: Fifty years of residual insecticide spraying to control Triatoma infestans in the Gran Chaco region of northern Argentina, Paraguay and Bolivia shows that vertically coordinated interventions aiming at full coverage have limited effects and are unsustainable. We quantified the spatial distribution of T. infestans domestic infestation at the district level, identified environmental factors associated with high infestation and then explored the usefulness of risk maps for the spatial stratification of interventions. Methods and Findings: We performed spatial analyses of house infestation data collected by the National Chagas Service in Moreno Department, northern Argentina (1999-2002). Clusters of high domestic infestation occurred in the southwestern extreme of the district. A multi-model selection approach showed that domestic infestation clustered in areas of low elevation, with few farmlands, high density of rural houses, high mean maximum land surface temperature, large NDVI, and high percentage of degraded and deforested lands. The best model classified 98.4% of the communities in the training dataset (sensitivity, 93.3%; specificity, 95.4%). The risk map evidenced that the high-risk area only encompassed 16% of the district. By building a network-based transportation model we assessed the operational costs of spatially contiguous and spatially targeted interventions. Targeting clusters of high infestation would have reached ~80% of all communities slated for full-coverage insecticide spraying, reducing in half the total time and economic cost incurred by a spatially contiguous strategy. Conclusions and Significance: In disperse rural areas where control programs can accomplish limited coverage, consideration of infestation hot spots can contribute to the design and execution of cost-effective interventions against Chagas disease vectors. If field validated, targeted vertical control in high risk areas and horizontal control in medium to low risk areas may provide both a logistically and economically feasible alternative to blanket vertical insecticide spraying when resources are limited.Fil: Vazquez Prokopec, Gonzalo Martin. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. University of Emory; Estados Unidos. Fogarty International Center; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Spillmann, Cynthia. Ministerio de Salud. Coordinación Nacional de Control de Vectores; ArgentinaFil: Zaidenberg, Mario. Ministerio de Salud. Coordinación Nacional de Control de Vectores; ArgentinaFil: Gurtler, Ricardo Esteban. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kitron, Uriel. University of Emory; Estados Unidos. Fogarty International Center; Estados Unido

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

Effectiveness of residual spraying of peridomestic ecotopes with deltamethrin and permethrin on Triatoma infestans in rural western Argentina: a district-wide randomized trial

OBJECTIVE: To compare the effectiveness of a single residual spraying of pyrethroids on the occurrence and abundance of Triatoma infestans in peridomestic ecotopes in rural La Rioja. METHODS: A total of 667 (32.8%) peridomestic sites positive for T. infestans in May 1999 were randomly assigned to treatment within each village, sprayed in December 1999, and reinspected in December 2000. Treatments included 2.5% suspension concentrate (SC) deltamethrin in water at 25 mg active ingredient (a.i.)/m² applied with: (a) manual compression sprayers (standard treatment) or (b) power sprayers; (c) 1.5% emulsifiable concentrate (EC) deltamethrin at 25 mg a.i./m²; and (d) 10% EC cis-permethrin at 170 mg a.i./m². EC pyrethroids were diluted in soybean oil and applied with power sprayers. All habitations were sprayed with the standard treatment. FINDINGS: The prevalence of T. infestans 1-year post-spraying was significantly lower in sites treated with SC deltamethrin applied with manual (24%) or power sprayers (31%) than in sites treated with EC deltamethrin (40%) or EC permethrin (53%). The relative odds of infestation and catch of T. infestans 1-year post-spraying significantly increased with the use of EC pyrethroids, the abundance of bugs per site before spraying, total surface, and host numbers. All insecticides had poor residual effects on wooden posts. CONCLUSION: Most of the infestations probably originated from triatomines that survived exposure to insecticides at each site. Despite the standard treatment proving to be the most effective, the current tactics and procedures fail to eliminate peridomestic populations of T. infestans in semiarid rural areas and need to be revised

Effectiveness of residual spraying of peridomestic ecotopes with deltamethrin and permethrin on Triatoma infestans in rural western Argentina: a district-wide randomized trial.

OBJECTIVE: To compare the effectiveness of a single residual spraying of pyrethroids on the occurrence and abundance of Triatoma infestans in peridomestic ecotopes in rural La Rioja. METHODS: A total of 667 (32.8%) peridomestic sites positive for T. infestans in May 1999 were randomly assigned to treatment within each village, sprayed in December 1999, and reinspected in December 2000. Treatments included 2.5% suspension concentrate (SC) deltamethrin in water at 25 mg active ingredient (a.i.)/m(2) applied with: (a) manual compression sprayers (standard treatment) or (b) power sprayers; (c) 1.5% emulsifiable concentrate (EC) deltamethrin at 25 mg a.i./m(2); and (d) 10% EC cis-permethrin at 170 mg a.i./m(2). EC pyrethroids were diluted in soybean oil and applied with power sprayers. All habitations were sprayed with the standard treatment. FINDINGS: The prevalence of T. infestans 1-year post-spraying was significantly lower in sites treated with SC deltamethrin applied with manual (24%) or power sprayers (31%) than in sites treated with EC deltamethrin (40%) or EC permethrin (53%). The relative odds of infestation and catch of T. infestans 1-year post-spraying significantly increased with the use of EC pyrethroids, the abundance of bugs per site before spraying, total surface, and host numbers. All insecticides had poor residual effects on wooden posts. CONCLUSION: Most of the infestations probably originated from triatomines that survived exposure to insecticides at each site. Despite the standard treatment proving to be the most effective, the current tactics and procedures fail to eliminate peridomestic populations of T. infestans in semiarid rural areas and need to be revised

Effectiveness of residual spraying of peridomestic ecotopes with deltamethrin and permethrin on Triatoma infestans in rural western Argentina: a district-wide randomized trial

Fil: Gürtler, Ricardo E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Laboratorio de Ecología General; Argentina.Fil: Canale, Delmi M. Coordinación Nacional de Control de Vectores; Argentina.Fil: Spillmann, Cynthia. Coordinación Nacional de Control de Vectores; Argentina.Fil: Stariolo, Raúl. Coordinación Nacional de Control de Vectores; Argentina.Fil: Salomón, Oscar D. ANLIS Dr.C.G.Malbrán. Centro Nacional de Diagnóstico e Investigación de Endemo-Epidemias; Argentina.Fil: Blanco, Sonia. Coordinación Nacional de Control de Vectores; Argentina.Fil: Segura, Elsa L. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Objective: To compare the effectiveness of a single residual spraying of pyrethroids on the occurrence and abundance of Triatoma infestans in peridomestic ecotopes in rural La Rioja. Methods: A total of 667 (32.8%) peridomestic sites positive for T. infestans in May 1999 were randomly assigned to treatment within each village, sprayed in December 1999, and reinspected in December 2000. Treatments included 2.5% suspension concentrate (SC) deltamethrin in water at 25 mg active ingredient (a.i.)/m(2) applied with: (a) manual compression sprayers (standard treatment) or (b) power sprayers; (c) 1.5% emulsifiable concentrate (EC) deltamethrin at 25 mg a.i./m(2); and (d) 10% EC cis-permethrin at 170 mg a.i./m(2). EC pyrethroids were diluted in soybean oil and applied with power sprayers. All habitations were sprayed with the standard treatment. Findings: The prevalence of T. infestans 1-year post-spraying was significantly lower in sites treated with SC deltamethrin applied with manual (24%) or power sprayers (31%) than in sites treated with EC deltamethrin (40%) or EC permethrin (53%). The relative odds of infestation and catch of T. infestans 1-year post-spraying significantly increased with the use of EC pyrethroids, the abundance of bugs per site before spraying, total surface, and host numbers. All insecticides had poor residual effects on wooden posts. Conclusion: Most of the infestations probably originated from triatomines that survived exposure to insecticides at each site. Despite the standard treatment proving to be the most effective, the current tactics and procedures fail to eliminate peridomestic populations of T. infestans in semiarid rural areas and need to be revised