title: Differential West Nile fever ascertainment in the United States: a multilevel analysis.
abstract: We evaluated the completeness of West Nile fever (WNF) surveillance within the U.S. public health system. We surveyed laboratory and surveillance programs on policies, practices, and capacities for testing, confirmation, and reporting (collectively called ascertainment) from 2003 through 2005. We calculated syndrome ascertainment ratios by dividing WNF counts by neuroinvasive disease counts; separately, we performed multilevel modeling. Jurisdictions were more likely to ascertain at least one WNF cases per West Nile neuroinvasive disease case when ≤ 1 testing restrictions existed (odds ratio [OR] = 7.7, 95% confidence interval [CI] = 1.3-46.4), when conducting ≥ 4 activities to enhance reporting (OR = 9.3, 95% CI = 1.6-54.8), and when ≥ 5.0 staff per million residents were dedicated to arboviral surveillance (OR = 6.4, 95% CI = 1.0-40.3). Ascertainment of WNF was less likely among Blacks (OR = 0.56, 95% CI = 0.31-0.99) and Hispanics (OR = 0.69, 95% CI = 0.48-0.98) than among Whites. Ascertainment was more complete when testing and reporting were enhanced, but differentially incomplete for minorities.
authors.affiliation: Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA. bsilk@cdc.gov
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Silk
authors.forename: J Rex
authors.initials: JR
authors.lastname: Astles
authors.forename: Jaime
authors.initials: J
authors.lastname: Hidalgo
authors.forename: Rosemary
authors.initials: R
authors.lastname: Humes
authors.forename: Lance A
authors.initials: LA
authors.lastname: Waller
authors.forename: James W
authors.initials: JW
authors.lastname: Buehler
authors.forename: Ruth L
authors.initials: RL
authors.lastname: Berkelman
mesh_terms: D001741:Black or African American; D006630:Hispanic or Latino; D006801:Humans; D016017:Odds Ratio; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014901:West Nile Fever / Q000175:diagnosis* / Q000453:epidemiology*; D044465:White People