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Powassan virus encephalitis, Minnesota, USA

Justin Birge1, Steven Sonnesyn

  • 1Abbott Northwestern Hospital, Minneapolis, Minnesota, USA. birgejustin@gmail.com

Emerging Infectious Diseases
|September 29, 2012
PubMed

Insights

Powassan virus (POWV) causes rare tick-borne encephalitis in North America. Increased cases in Minnesota and Wisconsin, including a fatal encephalitis case, highlight the need for suspecting POWV in tick-exposed patients.

Area of Science:

  • * Neuroscience
  • * Infectious Diseases
  • * Public Health

Background:

  • * Powassan virus (POWV) is a rare tick-borne flavivirus responsible for encephalitis in North America.
  • * Historically, confirmed POWV cases were concentrated in the northeastern United States.
  • * Recent years have seen an increase in confirmed POWV cases in Minnesota and Wisconsin.

Observation:

  • * A fatal case of POWV encephalitis occurred in Minnesota.
  • * The patient had a history of tick exposure.
  • * Clinical presentation was consistent with viral encephalitis.

Findings:

  • * Laboratory confirmation of Powassan virus as the causative agent of encephalitis.
  • * The case represents a severe outcome of POWV infection.
  • * Geographic distribution of POWV appears to be expanding or increasing in the upper Midwest.

Implications:

  • * Clinicians should consider POWV in the differential diagnosis of viral encephalitis, especially in tick-endemic areas.
  • * Public health awareness regarding tick-borne illnesses and preventative measures is crucial.
  • * Further surveillance and research are needed to understand the epidemiology and clinical spectrum of POWV in the United States.

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