Volume 78, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Assessments of spatial risk of exposure to vector-borne pathogens that combine vector and human disease data are needed for areas encompassing large tracts of public land with low population bases. We addressed this need for West Nile virus (WNV) disease in the northern Colorado Front Range by developing not only a spatial model for entomological risk of exposure to WNV vectors and an epidemiological risk map for WNV disease but also a novel risk-classification index combining data for these independently derived measures of entomological and epidemiological risk. Risk of vector exposure was high in the densely populated eastern plains portion of the Front Range but low in cooler montane areas to the west that are sparsely populated but used heavily for recreation in the summer. The entomological risk model performed well when applied to the western, mountainous part of Colorado and validated against epidemiologic data.


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  1. Goddard LB, Roth AE, Reisen WK, Scott TW, 2002. Vector competence of California mosquitoes for West Nile virus. Emerg Infect Dis 8 : 1385–1391. [Google Scholar]
  2. Turell MJ, Dohm DJ, Sardelis MR, O’Guinn ML, Andreadis TG, Blow JA, 2005. An update on the potential of North American mosquitoes (Diptera: Culicidae) to transmit West Nile virus. J Med Entomol 42 : 57–62. [Google Scholar]
  3. Turell MJ, Sardelis MR, O’Guinn ML, Dohm DJ, 2002. Potential vectors of West Nile virus in North America. Curr Top Microbiol Immunol 267 : 241–252. [Google Scholar]
  4. Bolling BG, Moore CG, Anderson SL, Blair CD, Beaty BJ, 2007. Entomological studies along the Colorado Front Range during a period of intense West Nile virus activity. J Am Mosq Contr Assoc 23 : 37–46. [Google Scholar]
  5. Smith GC, Moore CG, Davis T, Savage HM, Thapa AB, Shrestha SL, Karabatsos N, 1993. Arbovirus surveillance in northern Colorado, 1987 and 1991. J Med Entomol 30 : 257–261. [Google Scholar]
  6. Gujral IB, Zielinski-Gutierrez EC, LeBailly A, Nasci R, 2007. Behavioral risks for West Nile virus disease, northern Colorado, 2003. Emerg Infect Dis 13 : 419–425. [Google Scholar]
  7. Tempelis CH, Francy DB, Hayes RO, Lofy MF, 1967. Variations in feeding patterns of seven culicine mosquitoes on vertebrate hosts in Weld and Larimer counties, Colorado. Am J Trop Med Hyg 16 : 111–119. [Google Scholar]
  8. Tsai TF, Smith GC, Happ CM, Kirk LJ, Jakob WL, Bolin RA, Francy DB, Lampert KJ, 1989. Surveillance of St. Louis encephalitis virus vectors in Grand Junction, Colorado, in 1987. J Am Mosq Contr Assoc 5 : 161–165. [Google Scholar]
  9. Tsai TF, Smith GC, Ndukwu M, Jakob WL, Happ CM, Kirk LJ, Francy DB, Lampert KJ, 1988. Entomologic studies after a St. Louis encephalitis epidemic in Grand Junction, Colorado. Am J Epidemiol 128 : 285–297. [Google Scholar]
  10. Reisen WK, Lothrop HD, 1995. Population ecology and dispersal of Culex tarsalis (Diptera: Culicidae) in the Coachella Valley of California. J Med Entomol 32 : 490–502. [Google Scholar]
  11. Wegbreit J, Reisen WK, 2000. Relationships among weather, mosquito abundance, and encephalitis virus activity in California: Kern County 1990–98. J Am Mosq Contr Assoc 16 : 22–27. [Google Scholar]
  12. Hess AD, Hayes RO, 1970. Relative potentials of domestic animals for zooprophylaxis against mosquito vectors of encephalitis. Am J Trop Med Hyg 19 : 327–334. [Google Scholar]
  13. Lothrop HD, Reisen WK, 2001. Landscape affects the host-seeking patterns of Culex tarsalis (Diptera: Culicidae) in the Coachella Valley of California. J Med Entomol 38 : 325–332. [Google Scholar]
  14. Baker M, 1961. The altitudinal distribution of mosquito larvae in the Colorado Front Range. Trans. Am. Entomol. Soc. 87 : 231–246. [Google Scholar]
  15. Harmston FC, Lawson FA, 1967. Mosquitoes of Colorado. Atlanta, GA: U.S. Department of Health, Education and Welfare, Public Health Service.
  16. Carpenter SJ, 1969. Observations on the distribution and ecology of mountain Aedes mosquitoes in California. XII. Other species found in the mountains. Calif. Vector Views 16 : 27–34. [Google Scholar]
  17. Darsie RF Jr, Ward RA, 2005. Identification and Geographical Distribution of the Mosquitoes of North America, North of Mexico. Gainesville, FL: University Press of Florida.
  18. Bailey SM, Eliason DA, Hoffman BL, 1965. Flight and dispersal of the mosquito Culex tarsalis Coquillett in the Sacramento Valley of California. Hilgardia 37 : 73–113. [Google Scholar]
  19. Dow RP, Reeves WC, Bellamy RE, 1965. Dispersal of female Culex tarsalis into a larvicided area. Am J Trop Med Hyg 14 : 656–670. [Google Scholar]
  20. Reisen WK, Milby MM, Meyer RP, Pfuntner AR, Spoehel J, Hazelrigg JE, Webb JP Jr, 1991. Mark–release–recapture studies with Culex mosquitoes (Diptera: Culicidae) in southern California. J Med Entomol 28 : 357–371. [Google Scholar]
  21. Sall J, Creighton L, Lehman A, 2005. JMP Start Statistics. Third edition. Belmont, CA: Brooks/Cole.
  22. Leung LR, Qian Y, Bian X, Washington WM, Han J, Roads JO, 2004. Mid-century ensemble regional climate change scenarios for the western United States. Clim Change 62 : 75–113. [Google Scholar]
  23. Diuk-Wasser MA, Brown HE, Andreadis TG, Fish D, 2006. Modeling the spatial distribution of mosquito vectors for West Nile virus in Connecticut, USA. Vector Borne Zoonotic Dis 6 : 283–295. [Google Scholar]
  24. Zou L, Miller SN, Schmidtmann ET, 2006. Mosquito larval habitat mapping using Remote Sensing and GIS: implications of coalbed methane development and West Nile virus. J Med Entomol 43 : 1034–1041. [Google Scholar]
  25. Shone SM, Ferrao PN, Lesser CR, Norris DE, Glass GE, 2001. Analysis of mosquito vector species abundances in Maryland using geographic information systems. Ann NY Acad Sci 951 : 364–368. [Google Scholar]
  26. Shaman J, Stieglitz M, Stark C, Le Blancq S, Cane M, 2002. Using a dynamic hydrology model to predict mosquito abundances in flood and swamp water. Emerg Infect Dis 8 : 6–13. [Google Scholar]
  27. Rios J, Hacker CS, Hailey CA, Parsons RE, 2006. Demographic and spatial analysis of West Nile virus and St. Louis encephalitis in Houston, Texas. J Am Mosq Contr Assoc 22 : 254–263. [Google Scholar]
  28. Kronenwetter-Koepel TA, Meece JK, Miller CA, Reed KD, 2005. Surveillance of above- and below-ground mosquito breeding habitats in a rural Midwestern community: baseline data for larvicidal control measures against West Nile virus vectors. Clin Med Res 3 : 3–12. [Google Scholar]
  29. Gibbs SEJ, Wimberly MC, Madden M, Masour J, Yabsley MJ, Stallknecht DE, 2006. Factors affecting the geographic distribution of West Nile virus in Georgia, USA: 2002–2004. Vector Borne Zoonotic Dis 6 : 73–82. [Google Scholar]
  30. Theophilides CN, Ahearn SC, Grady S, Merlino M, 2003. Identifying West Nile virus risk areas: the dynamic continuous-area space–time system. Am J Epidemiol 157 : 843–854. [Google Scholar]
  31. Ward MP, 2006. Spread of equine West Nile virus encephalomyelitis during the 2002 Texas epidemic. Am J Trop Med Hyg 74 : 1090–1095. [Google Scholar]
  32. Ward MP, Ramsay BH, Gallo K, 2005. Rural cases of equine West Nile virus encephalomyelitis and the normalized difference vegetation index. Vector Borne Zoonotic Dis 5 : 181–188. [Google Scholar]
  33. Brownstein JS, Rosen H, Purdy D, Miller JR, Merlino M, Mostashari F, Fish D, 2002. Spatial analysis of West Nile virus: rapid risk assessment of an introduced vector-borne zoonosis. Vector Borne Zoonotic Dis 2 : 157–164. [Google Scholar]
  34. Corrigan RLA, Waldner C, Epp T, Wright J, Whitehead SM, Bangura H, Young E, Townsend HGG, 2006. Prediction of human cases of West Nile virus by equine cases, Saskatchewan, Canada, 2003. Prev Vet Med 76 : 263–272. [Google Scholar]
  35. Yiannakoulias NW, Schopflocher DP, Svenson LW, 2006. Modelling geographic variations in West Nile virus. Can J Publ Health 97 : 374–378. [Google Scholar]
  36. Ruiz MO, Tedesco C, McTighe T, Austin C, Kitron U, 2004. Environmental and social determinants of human risk during a West Nile virus outbreak in the greater Chicago area, 2002. Int J Health Geogr 3 : 8–19. [Google Scholar]
  37. Ruiz MO, Walker ED, Foster ES, Haramis LD, Kitron U, 2007. Association of West Nile virus illness and urban landscapes in Chicago and Detroit. Int J Health Geogr 6 : 10–20. [Google Scholar]
  38. Ward MR, Stallknecht DE, Willis J, Conroy MJ, Davidson WR, 2006. Wild bird mortality and West Nile virus surveillance: biases associated with detection, reporting, and carcass persistence. J Wildl Dis 42 : 92–106. [Google Scholar]
  39. Patnaik JL, Juliusson L, Vogt RL, 2007. Environmental predictors of human West Nile virus infections, Colorado. Emerg Infect Dis 13 : 1788–1790. [Google Scholar]
  40. Eisen L, Eisen RJ, 2007. Need for improved methods to collect and present spatial epidemiologic data for vectorborne diseases. Emerg Infect Dis 13 : 1816–1820. [Google Scholar]
  41. Eisen RJ, Eisen L, 2008. Spatial modeling of human risk of exposure to vector-borne pathogens based on epidemiological versus arthropod vector data. J Med Entomol 45 : 181–192. [Google Scholar]
  42. Lothrop HD, Reisen WK, 1999. A geographical information system to manage mosquito and arbovirus surveillance and control data in the Coachella Valley of California. J Am Mosq Contr Assoc 15 : 299–307. [Google Scholar]
  43. Takeda T, Whitehouse CA, Brewer M, Gettman AD, Mather TN, 2003. Arbovirus surveillance in Rhode Island: assessing potential ecologic and climatic correlates. J Am Mosq Contr Assoc 19 : 179–189. [Google Scholar]
  44. Brownstein JS, Holford TR, Fish D, 2004. Enhancing West Nile virus surveillance, United States. Emerg Infect Dis 10 : 1129–1133. [Google Scholar]
  45. Cooke W III, Grala K, Wallis R, 2006. Avian GIS models signal human risk for West Nile virus in Mississippi. Int J Health Geogr 5 : 36–56. [Google Scholar]
  46. Kutz FW, Wade TG, Pagac BB, 2003. A geospatial study of the potential of two exotic species of mosquitoes to impact the epidemiology of West Nile virus in Maryland. J Am Mosq Contr Assoc 19 : 190–198. [Google Scholar]
  47. Lukacik G, Anand M, Shusas EJ, Howard JJ, Oliver J, Chen H, Backenson PB, Kauffman EB, Bernard KA, Kramer LD, White DJ, 2006. West Nile virus surveillance in mosquitoes in New York State, 2000–2004. J Am Mosq Contr Assoc 22 : 264–271. [Google Scholar]
  48. Mongoh MN, Kaitsa ML, Dyer NW, 2006. Environmental and ecological determinants of West Nile virus occurrence in horses in North Dakota, 2002. Epidemiol Infect 135 : 57–66. [Google Scholar]
  49. Orme-Zavaleta J, Jorgensen J, D’Ambrosio B, Altendorf E, Rossignol PA, 2006. Discovering spatio-temporal models of the spread of West Nile virus. Risk Anal 26 : 413–422. [Google Scholar]
  50. Eisen RJ, Lane RS, Fritz CL, Eisen L, 2006. Spatial patterns of Lyme disease risk in California based on disease incidence data and modeling of vector-tick exposure. Am J Trop Med Hyg 75 : 669–676. [Google Scholar]

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  • Received : 12 Jun 2007
  • Accepted : 30 Dec 2007

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