Volume 91, Issue 2
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



During 2012, four north-central Texas counties experienced high West Nile virus (WNV) disease incidence. Aerial insecticide spraying was conducted in two counties. To evaluate the effect of spraying on WNV disease, we calculated incidence rate ratios (IRRs) in treated and untreated areas by comparing incidence before and after spraying; for unsprayed areas, before and after periods were defined by using dates from a corresponding sprayed area. In treated areas, WNV neuroinvasive disease incidence before and after spraying was 7.31/100,000 persons and 0.28/100,000 persons, respectively; the IRR was 26.42 (95% confidence interval [CI]: 12.42–56.20). In untreated areas, the before and after incidence was 4.80/100,000 persons and 0.45/100,000 persons, respectively; the IRR was 10.57 (95% CI: 6.11–18.28). The ratio of IRRs was 2.50 (95% CI: 0.98–6.35). Disease incidence decreased in both areas, but the relative change was greater in aerial-sprayed areas.


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  1. Centers for Disease Control and Prevention (CDC), 2010. Surveillance for human West Nile virus disease—United States, 1999–2008. MMWR Surveill Summ 59: 117.
  2. Petersen LR, Brault AC, Nasci RS, , 2013. West Nile virus: review of the literature. JAMA 310: 308315.[Crossref]
  3. Centers for Disease Control and Prevention (CDC), 2013. West Nile virus disease and other arboviral diseases—United States, 2012. MMWR Morb Mortal Wkly Rep 62: 513517.
  4. Centers for Disease Control and Prevention (CDC), 2011. Arboviral neuroinvasive and non-neuroinvasive diseases. Nationally notifiable diseases and conditions and current case definitions. Atlanta, GA: CDC. Available at: http://www.cdc.gov/nndss/script/ConditionSummary.aspx?CondID=17. Accessed January 17, 2014.
  5. U.S. Census Bureau, 2010. Census. Available at: http://factfinder2.census.gov/faces/nav/jsf/pages/index.xhtml. Accessed January 6, 2014.
  6. 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 G, , 2001. Epidemic West Nile encephalitis, New York, 1999: results of a household-based seroepidemiological survey. Lancet 358: 261264.[Crossref]
  7. Busch MP, Wright DJ, Custer B, Tobler LH, Stramer SL, Kleinman SH, Prince HE, Bianco C, Foster G, Petersen LR, Nemo G, Glynn SA, , 2006. West Nile virus infections projected from blood donor screening data, United States, 2003. Emerg Infect Dis 12: 395402.[Crossref]
  8. Elnaiem DE, Kelley K, Wright S, Laffey R, Yoshimura G, Reed M, Goodman G, Thiemann T, Reimer L, Reisen WK, Brown D, , 2008. Impact of aerial spraying of pyrethrin insecticide on Culex pipiens and Culex tarsalis (Diptera: Culicidae) abundance and West Nile virus infection rates in an urban/suburban area of Sacramento County, California. J Med Entomol 45: 751757.[Crossref]
  9. Mount GA, Biery TL, Haile DG, , 1996. A review of ultralow-volume aerial sprays of insecticide for mosquito control. J Am Mosq Control Assoc 12: 601618.
  10. Macedo PA, Schleier JJ, 3rd Reed M, Kelley K, Goodman GW, Brown DA, Peterson RK, , 2010. Evaluation of efficacy and human health risk of aerial ultra-low volume applications of pyrethrins and piperonyl butoxide for adult mosquito management in response to West Nile virus activity in Sacramento County, California. J Am Mosq Control Assoc 26: 5766.[Crossref]
  11. Hopkins CC, Hollinger FB, Johnson RF, Dewlett HJ, Newhouse VF, Chamberlain RW, , 1975. The epidemiology of St. Louis encephalitis in Dallas, Texas, 1966. Am J Epidemiol 102: 115.[Crossref]
  12. Carney RM, Husted S, Jean C, Glaser C, Kramer V, , 2008. Efficacy of aerial spraying of mosquito adulticide in reducing incidence of West Nile virus, California, 2005. Emerg Infect Dis 14: 747754.[Crossref]
  13. Geraghty EM, Margolis HG, Kjemtrup A, Reisen W, Franks P, , 2013. Correlation between aerial insecticide spraying to interrupt West Nile virus transmission and emergency department visits in Sacramento County, California. Public Health Rep 128: 221230.[Crossref]
  14. Chung WM, Buseman CM, Joyner SN, Hughes SM, Fomby TB, Luby JP, Haley RW, , 2013. The 2012 West Nile encephalitis epidemic in Dallas, Texas. JAMA 310: 297307.[Crossref]
  15. Andis MD, Sackett SR, Carroll MK, Bordes ES, , 1987. Strategies for the emergency control of arboviral epidemics in New Orleans. J Am Mosq Control Assoc 3: 125130.
  16. Centers for Disease Control and Prevention, 2013. West Nile Virus in the United States: Guidelines for Surveillance, Prevention, and Control. Available at: http://www.cdc.gov/westnile/resources/pdfs/wnvGuidelines.pdf. Accessed January 6, 2014.

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  • Received : 03 Feb 2014
  • Accepted : 28 Mar 2014

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