Volume 79, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


In the absence of a vaccine for use in humans against West Nile virus (WNV), mosquito control and personal protection against mosquito bites are the only measures available to prevent disease. Improved spatial targeting is desirable for costly mosquito and WNV surveillance and control schemes. We used a multivariate regression modeling approach to develop spatial models predicting high risk of exposure to WNV in western and eastern Colorado based on associations between Geographic Information System–derived environmental data and zip code of residence for 3,659 human WNV disease cases from 2002 to 2006. Models were robust, with user accuracies for correct classification of high risk areas of 67–80%. The importance of selecting a suitable model development area in an ecologically and climatically diverse environment was shown by models based on data from the eastern plains landscape performing poorly in the mountainous western part of Colorado and .


Article metrics loading...

Loading full text...

Full text loading...



  1. Nash D, Mostashari F, Fine A, Miller J, O’Leary D, Murray K, Huang A, Rosenberg A, Greenberg A, Sherman M, Wong S, Layton M, 2001. The outbreak of West Nile virus infection in the New York City area in 1999. N Engl J Med 344 : 1807–1814.
  2. Hayes EB, Komar N, Nasci RS, Montgomery SP, O’Leary DR, Campbell GL, 2005. Epidemiology and transmission dynamics of West Nile virus disease. Emerg Infect Dis 11 : 1167–1173.
  3. Colorado Department of Public Health and Environment, West Nile Virus. Available at: http://www.cdphe.state.co.us/dc/zoonosis/wnv/. Accessed August 8, 2007.
  4. Turell MJ, Dohm DJ, Sardelis MR, Oguinn 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.
  5. Goddard LB, Roth AE, Reisen WK, Scott TW, 2002. Vector competence of California mosquitoes for West Nile virus. Emerg Infect Dis 8 : 1385–1391.
  6. Reisen W, Lothrop H, Chiles R, Madon M, Cossen C, Woods L, Husted S, Kramer V, Edman J, 2004. West Nile virus in California. Emerg Infect Dis 10 : 1369–1378.
  7. Monath TP, 2001. Prospects for development of a vaccine against the West Nile virus. Ann NY Acad Sci 951 : 1–12.
  8. Gould LH, Fikrig E, 2004. West Nile virus: a growing concern? J Clin Invest 113 : 1102–1107.
  9. Mason PW, Shustov AV, Frolov I, 2006. Production and characterization of vaccines based on flaviviruses defective in replication. Virology 351 : 432–443.
  10. Granwehr BP, Lillibridge KM, Higgs S, Mason PW, Aronson JF, Campbell GA, Barrett AD, 2004. West Nile virus: where are we now? Lancet Infect Dis 4 : 547–556.
  11. Petersen LR, Marfin AA, 2002. West Nile virus: a primer for the clinician. Ann Intern Med 137 : 173–179.
  12. Sampathkumar P, 2003. West Nile virus: Epidemiology, clinical presentation, diagnosis, and prevention. Mayo Clin Proc 78 : 1137–1144.
  13. Herrington J, 2003. Pre-West Nile virus outbreak: perceptions and practices to prevent mosquito bites and viral encephalitis in the United States. Vector Borne Zoonotic Dis 3 : 157–173.
  14. Winters AM, Bolling BG, Beaty BJ, Blair CD, Eisen RJ, Meyer AM, Pape WJ, Moore CG, Eisen L, 2008. Combining mosquito vector and human disease data for improved assessment of spatial West Nile virus disease risk. Am J Trop Med Hyg 78 : 654–665.
  15. Wegbreit J, Reisen WK, 2000. Relationships among weather, mosquito abundance, and encephalitis virus activity in California: Kern County 1990–98. J Am Mosq Control Assoc 16 : 22–27.
  16. Reisen WK, Lothrop HD, Hardy JL, 1995. Bionomics of Culex tarsalis (Diptera: Culicidae) in relation to arbovirus transmission in southeastern California. J Med Entomol 32 : 316–327.
  17. Reisen WK, 1995. Effect of temperature on Culex tarsalis (Diptera: Culicidae) from the Coachella and San Joaquin Valleys of California. J Med Entomol 32 : 636–645.
  18. Reisen WK, Fang Y, Martinez VM, 2006. Effects of temperature on the transmission of West Nile virus by Culex tarsalis (Diptera: Culicidae). J Med Entomol 43 : 309–317.
  19. Reisen WK, Lothrop HD, Presser SB, Hardy JL, Gordon EW, 1997. Landscape ecology of arboviruses in southeastern California—temporal and spatial patterns of enzootic activity in Imperial Valley, 1991–1994. J Med Entomol 34 : 179–188.
  20. Reisen WK, Lothrop HD, Presser SB, Milby MM, Hardy JL, Wargo MJ, Emmons RW, 1995. Landscape ecology of arboviruses in southern California—temporal and spatial patterns of vector and virus activity in Coachella Valley, 1990–1992. J Med Entomol 32 : 255–266.
  21. 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 Control Assoc 23 : 37–46.
  22. 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.
  23. Eidson M, Kramer L, Stone W, Hagiwara Y, Schmit K, 2001. Dead bird surveillance as an early warning system for West Nile virus. Emerg Infect Dis 7 : 631–635.
  24. Eidson M, Komar N, Sorhage F, Nelson R, Talbot T, Mostashari F, McLean R, 2001. Crow deaths as a sentinel surveillance system for West Nile virus in the northeastern United States, 1999. Emerg Infect Dis 7 : 615–620.
  25. Mostashari F, Kulldorff M, Hartman JJ, Miller JR, Kulasekera V, 2003. Dead bird clusters as an early warning system for West Nile virus activity. Emerg Infect Dis 9 : 641–646.
  26. Julian KG, Eidson M, Kipp AM, Weiss E, Petersen LR, Miller JR, Hinten SR, Marfin AA, 2002. Early season crow mortality as a sentinel for West Nile virus disease in humans, northeastern United States. Vector Borne Zoonotic Dis 2 : 145–155.
  27. Guptill SC, Julian KG, Campbell GL, Price SD, Marfin AA, 2003. Early-season avian deaths from West Nile virus as warnings of human infection. Emerg Infect Dis 9 : 483–484.
  28. Nemeth NM, Beckett S, Edwards E, Klenk K, Komar N, 2007. Avian mortality surveillance for West Nile virus in Colorado. Am J Trop Med Hyg 76 : 431–437.
  29. 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.
  30. DiMenna MA, Bueno R Jr, Parmenter RR, Norris DE, Sheyka JM, Molina JL, LaBeau EM, Hatton ES, Glass GE, 2006. Emergence of West Nile virus in mosquito (Diptera: Culicidae) communities of the New Mexico Rio Grande Valley. J Med Entomol 43 : 594–599.
  31. DiMenna MA, Bueno R Jr, Parmenter RR, Norris DE, Sheyka JM, Molina JL, Labeau EM, Hatton ES, Roberts CM, Glass GE, 2007. Urban habitat evaluation for West Nile virus surveillance in mosquitoes in Albuquerque, New Mexico. J Am Mosq Contr Assoc 23 : 153–160.
  32. Ruiz M, 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.
  33. 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.
  34. Godsey MS Jr, Blackmore MS, Panella NA, Burkhalter K, Gottfried K, Halsey LA, Rutledge R, Langevin SA, Gates R, Lamonte KM, Lambert A, Lanciotti RS, Blackmore CG, Loyless T, Stark L, Oliveri R, Conti L, Komar N, 2005. West Nile virus epizootiology in the southeastern United States, 2001. Vector Borne Zoonotic Dis 5 : 82–89.
  35. White DJ, 2001. Vector surveillance for West Nile virus. Ann NY Acad Sci 951 : 74–83.
  36. Western Regional Climate Center, Climate of Colorado. Available at: http://www.wrcc.dri.edu/. Accessed August, 2007.
  37. Hayes EB, Sejvar JJ, Zaki SR, Lanciotti RS, Bode AV, Campbell GL, 2005. Virology, pathology, and clinical manifestations of West Nile virus disease. Emerg Infect Dis 11 : 1174–1179.
  38. Burnham K, Anderson D, 2002. Model Selection and Multimodel Inference: A Practical Information-Theoretic Approach. New York: Springer.
  39. Sall J, Creighton L, Lehman A, 2005. JMP Start Statistics. Third edition. Belmont: Brooks/Cole.
  40. Congalton R, Green K, 1999. Assessing the Accuracy of Remotely Sensed Data: Principles and Practices. Boca Raton, FL: Lewis Publishers.
  41. Higgs S, Schneider BS, Vanlandingham DL, Klingler KA, Gould EA, 2005. Nonviremic transmission of West Nile virus. Proc Natl Acad Sci USA 102 : 8871–8874.
  42. Centers for Disease Control and Prevention, West Nile virus. Available at: http://www.cdc.gov/ncidod/dvbid/westnile/. Accessed September 21, 2007.
  43. Miramontes R, Lafferty WE, Lind BK, Oberle MW, 2006. Is agricultural activity linked to the incidence of human West Nile virus? Am J Prev Med 30 : 160–163.
  44. Kilpatrick AM, Kramer LD, Campbell SR, Alleyne EO, Dobson AP, Daszak P, 2006. West Nile virus epidemics in North America are driven by shifts in mosquito feeding behavior. PLoS Biol 4 : 606–610.
  45. 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.
  46. Tempelis CH, Reeves WC, Bellamy RE, Lofy MF, 1965. A three-year study of the feeding habits of Culex tarsalis in Kern County, California. Am J Trop Med Hyg 14 : 170–177.
  47. Reisen WK, Meyer RP, Presser SB, Hardy JL, 1993. Effect of temperature on the transmission of western equine encephalomyelitis and St. Louis encephalitis viruses by Culex tarsalis (Diptera: Culicidae). J Med Entomol 30 : 151–160.
  48. Hagstrum DW, Workman EB, 1971. Interaction of temperature and feeding rate in determining the rate of development of larval Culex tarsalis (Diptera: Culicidae). Ann Entomol Soc Am 64 : 668–671.
  49. Kramer LD, Hardy JL, Presser SB, 1983. Effect of temperature of extrinsic incubation on the vector competence of Culex tarsalis for Western Equine encephalomyelitis virus. Am J Trop Med Hyg 32 : 1130–1139.
  50. Beehler JW, Mulla MS, 1995. Effects of organic enrichment on temporal distribution and abundance of culicine egg rafts. J Am Mosq Control Assoc 11 : 167–171.
  51. 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.
  52. Mostashari F, Bunning ML, Kitsutani PT, Singer DA, Nash D, Cooper MJ, Katz N, Liljebjelke KA, Biggerstaff BJ, Fine AD, Layton MC, Mullin SM, Johnson AJ, Martin DA, Hayes EB, Campbell GL, 2001. Epidemic West Nile encephalitis, New York, 1999: results of a household-based seroepidemiological survey. Lancet 358 : 261–264.
  53. 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.
  54. O’Leary DR, Marfin AA, Montgomery SP, Kipp AM, Lehman JA, Biggerstaff BJ, Elko VL, Collins PD, Jones JE, Campbell GL, Petersen LR, 2004. The epidemic of West Nile virus in the United States, 2002. Vector Borne Zoonotic Dis 4 : 61–70.
  55. 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.

Data & Media loading...

  • Received : 07 Dec 2007
  • Accepted : 03 Jun 2008

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error