title: Neuropsychological Impact of West Nile Virus Infection: An Extensive Neuropsychiatric Assessment of 49 Cases in Canada.
abstract: BACKGROUND
  West Nile virus emerged as an important human pathogen in North America and continues to pose a risk to public health. It can cause a highly variable range of clinical manifestations ranging from asymptomatic to severe illness. Neuroinvasive disease due to West Nile virus can lead to long-term neurological deficits and psychological impairment. However, these deficits have not been well described. The objective of this study was to characterize the neuropsychological manifestations of West Nile virus infection with a focus on neuroinvasive status and time since infection.
  
  
  METHODS
  Patients from Ontario Canada with a diagnosis of neuroinvasive disease (meningitis, encephalitis, or acute flaccid paralysis) and non-neuroinvasive disease who had participated in a cohort study were enrolled. Clinical and laboratory were collected, as well as demographics and medical history. Cognitive functioning was assessed using a comprehensive battery of neuropsychological tests.
  
  
  RESULTS
  Data from 49 individuals (32 with West Nile fever and 17 with West Nile neuroinvasive disease) were included in the present cross-sectional analysis. Patterns of neuropsychological impairment were comparable across participants with both neuroinvasive and non-neuroinvasive West Nile virus infection on all cognitive measures. Neuropsychiatric impairment was also observed more frequently at two to four years post-infection compared to earlier stages of illness.
  
  
  CONCLUSIONS
  Our data provide objective evidence for cognitive difficulties among patients who were infected with West Nile virus; these deficits appear to manifest regardless of severity of West Nile virus infection (West Nile fever vs. West Nile neuroinvasive disease), and are more prevalent with increasing illness duration (2-4 years vs. 1 month). Data from this study will help inform patients and healthcare providers about the expected course of recovery, as well as the need to implement effective treatment strategies that include neuropsychological interventions.
authors.affiliation: Department of Psychiatry & Behavioral Neurosciences, McMaster University, Hamilton, Ontario, Canada.|Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada.|Population Genomics Program, Chanchlani Research Centre, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Zainab
authors.initials: Z
authors.lastname: Samaan
authors.affiliation: Department of Psychiatry & Behavioral Neurosciences, McMaster University, Hamilton, Ontario, Canada.|Cleghorn Early Intervention in Psychosis Program, St. Joseph's Healthcare, Hamilton, Ontario, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: McDermid Vaz
authors.affiliation: Population Genomics Program, Chanchlani Research Centre, McMaster University, Hamilton, Ontario, Canada.|MiNDS Neuroscience Graduate Program, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Monica
authors.initials: M
authors.lastname: Bawor
authors.affiliation: Division of Infectious Diseases, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Tammy Hlywka
authors.initials: TH
authors.lastname: Potter
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Sasha
authors.initials: S
authors.lastname: Eskandarian
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada.|Division of Infectious Diseases, McMaster University, Hamilton, Ontario, Canada.|Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Mark
authors.initials: M
authors.lastname: Loeb
mesh_terms: D000328:Adult; D000368:Aged; D003072:Cognition Disorders / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario; D014901:West Nile Fever / Q000150:complications / Q000175:diagnosis*