Powassan Encephalitis


Powassan Encephalitis, Powassan Tick-Borne Encephalitis, Powassan Viral Encephalitis, Powassan Virus

  • Epidemiology
  1. Rare Encephalitis cause in Northeastern and North Central States
  • Pathophysiology
  1. Tickborne Illness via Woodchuck Tick or Groundhog Tick (Ixodes cookei, I. marxi or I. Scapularis)
  • Findings
  1. Presentations range from asymptomatic to severe neurologic Impairment
  • Labs
  1. Antibody to Powassan Virus (serum, CSF)
  • Differential Diagnosis
  • Management
  1. No known effective treatment
  2. Supportive care
  • Prognosis
  1. Cognitive Impairment in >50% of survivors, and 10-15% mortality