INVESTIGADORES
GURTLER Ricardo Esteban
artículos
Título:
Spatial heterogeneity and risk maps of community infestation by Triatoma infestans in rural northwestern Argentina.
Autor/es:
VAZQUEZ-PROKOPEC GM; SPILLMAN C; ZAIDENBERG M; GURTLER RE; KITRON U
Revista:
PLOS NEGLECTED TROPICAL DISEASES
Editorial:
PUBLIC LIBRARY SCIENCE
Referencias:
Lugar: San Francisco; Año: 2012 vol. 6 p. 1178 - 1190
ISSN:
1935-2735
Resumen:
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.