Neurological Complications Associated With the Powassan Virus and Treatment Interventions

Abstract

Powassan virus (POWV), a flavivirus transmitted by Ixodes ticks, poses significant neurological risks, including encephalitis and meningitis. Despite its growing geographical spread and severe clinical manifestations, no specific antiviral treatments are currently available. This review synthesizes the existing literature on POWV, focusing on its epidemiology, clinical manifestations, neurological impact, and current treatment approaches. The review also explores the molecular biology of POWV, highlighting its genomic structure and the role of nonstructural proteins in its pathogenesis. POWV infection can range from asymptomatic to severe neurological disorders such as encephalitis and meningitis, with the latter presenting less severe outcomes. The pathophysiology of the virus involves immune evasion and robust neuroinflammation, complicating treatment strategies. Current management is supportive, with efforts ongoing to repurpose existing antivirals and develop new therapeutic interventions. Prognostic disparities between POWV-induced meningitis and encephalitis are notable, with meningitis generally having more favorable outcomes. The review also identifies critical gaps in POWV research, particularly in understanding the long-term neurological impacts and developing specific antiviral therapies. This article collates existing relevant literature on the POWV and culminates in two strategic actions: firstly, in the absence of an existing vaccine, it proposes repurposing antiviral drugs designed for related flaviviruses to target shared molecular pathways, such as nonstructural proteins in the POWV. Secondly, the article advocates for longitudinal studies to explore the long-term neurological effects on individuals who have survived POWV infections.