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Treatment and prevention of West Nile virus infection

Lyle R Petersen, MD, MPH
Section Editor
Martin S Hirsch, MD
Deputy Editor
Jennifer Mitty, MD, MPH


West Nile virus, a member of the Japanese encephalitis virus antigenic complex, can lead to a wide range of clinical symptoms from asymptomatic disease to severe meningitis and encephalitis.

Management and prevention of West Nile virus is discussed below. The clinical manifestations and epidemiology of the infection are discussed elsewhere. (See "Epidemiology and pathogenesis of West Nile virus infection" and "Clinical manifestations and diagnosis of West Nile virus infection".)


Treatment of WN virus infection is primarily supportive. The potential use of several different therapeutic agents has been described [1-11]. However, only one controlled study to evaluate specific therapies for WN virus infection has been completed [11]. Uncontrolled studies or case reports suggesting treatment efficacy should be cautiously interpreted, since the clinical course and outcomes with WN virus neuroinvasive disease are highly variable [1,2].

Agents that have been considered include:

Interferon — The rationale for the use of alfa interferon is based upon evidence of efficacy against WN virus in vitro and in animal models [3-5].


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Literature review current through: Sep 2016. | This topic last updated: Apr 4, 2016.
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