MPH Graduate Student University of Nevada, Las Vegas Las Vegas, Nevada, United States
Mosquitoes serve as vectors of several arboviral diseases, even in the dry desert Southwest. West Nile Virus (WNV) was first reported in New York in 1999, and quickly spread across the US. Monitoring of mosquitoes by the local health district in Southern Nevada since 2004 confirms that most positive mosquitoes in the state are Culex (predominantly Cx. quinquefasciatus). We utilized health district reports, CDC reports, and patient case data from the Center for Health Information Analysis (CHIA) for Nevada for 2013-2017 to obtain a five-year snapshot of WNV human disease. The CHIA data represent all reported discharge data for inpatient, outpatient, and emergency department cases. Nearly 11,000 cases of vector-borne and parasitic human infections were recorded, and 121 were WNV. Most cases were from inpatient medical stays (70%) owing to high numbers of neuroinvasive cases. Inpatient stays for WNV are generally long (median = 12 days) and costly (median = $118,211). Sociodemographically, cases were predominantly white (74%), male (57%), and over the age of 60 (67%). Cases increased across years in all databases, though the percentage of positive test pools decreased after 2015. This analysis of WNV serves as a case study for using patient record databases as a means of indirect vector-borne disease surveillance that may prove to be useful for understanding the sociodemographic characteristics of patients at risk for vector-borne infections. Further, healthcare records may assist in obtaining population-based estimates of disease burden in the population and provide useful additional data for underfunded public health surveillance programs.
