Modifiable Risk Factors for West Nile Virus Infection during an Outbreak - Arizona, 2010

Division of Vector-borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado 80521, USA.
The American journal of tropical medicine and hygiene (Impact Factor: 2.7). 05/2012; 86(5):895-901. DOI: 10.4269/ajtmh.2012.11-0502
Source: PubMed


West Nile virus (WNV) is the leading cause of mosquito-borne disease in the United States; however, risk factors for infection are poorly defined. We performed a case-control study to identify modifiable risk factors for WNV infection. Case-patients (N = 49) had laboratory evidence of recent WNV infection, whereas control-subjects (N = 74) had negative WNV serology. We interviewed participants, surveyed households, and assessed environmental data. WNV infection was associated with living in or near Water District X within Gilbert Township (adjusted odds ratio [aOR] 5.2; 95% confidence interval [95% CI] = 1.5-18.1), having water-holding containers in their yard (aOR 5.0; 95% CI = 1.5-17.3), and not working or attending school outside the home (aOR 2.4; 95% CI = 1.1-5.5). During this outbreak, WNV infection was likely primarily acquired peri-domestically with increased risk associated with potential mosquito larval habitats around the home and neighborhood.

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