A country bug in the city: urban infestation by the Chagas disease vector Triatoma infestans in Arequipa, Peru
1 School of Geography and Development, The University of Arizona, 409 Harvill Building, 1103 East Second Street, Tucson, Arizona 85721, USA
2 Division of Epidemiology and Biostatistics, The University of Arizona, Roy P Drachman Hall, 1295 North Martin Avenue, PO Box 245211, Tucson, Arizona 85724, USA
3 Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Avenida Honorio Delgado 430, Urbanización Ingeniería, Lima, Peru
4 School of Animal and Comparative Biomedical Sciences, The University of Arizona, 1117 East Lowell Street, Tucson, Arizona 85721, USA
5 Bloomberg School of Public Health, Johns Hopkins University, 615 North Wolfe Street, Baltimore, Maryland 21205, USA
6 Department of Biostatistics and Epidemiology, University of Pennsylvania, 714 Blockley Hall, 423 Guardian Drive, Philadelphia, Pennsylvania 19104, USA
International Journal of Health Geographics 2013, 12:48 doi:10.1186/1476-072X-12-48Published: 30 October 2013
Interruption of vector-borne transmission of Trypanosoma cruzi remains an unrealized objective in many Latin American countries. The task of vector control is complicated by the emergence of vector insects in urban areas.
Utilizing data from a large-scale vector control program in Arequipa, Peru, we explored the spatial patterns of infestation by Triatoma infestans in an urban and peri-urban landscape. Multilevel logistic regression was utilized to assess the associations between household infestation and household- and locality-level socio-environmental measures.
Of 37,229 households inspected for infestation, 6,982 (18.8%; 95% CI: 18.4 – 19.2%) were infested by T. infestans. Eighty clusters of infestation were identified, ranging in area from 0.1 to 68.7 hectares and containing as few as one and as many as 1,139 infested households. Spatial dependence between infested households was significant at distances up to 2,000 meters. Household T. infestans infestation was associated with household- and locality-level factors, including housing density, elevation, land surface temperature, and locality type.
High levels of T. infestans infestation, characterized by spatial heterogeneity, were found across extensive urban and peri-urban areas prior to vector control. Several environmental and social factors, which may directly or indirectly influence the biology and behavior of T. infestans, were associated with infestation. Spatial clustering of infestation in the urban context may both challenge and inform surveillance and control of vector reemergence after insecticide intervention.