West Nile Virus (WNV) Infection and Encephalitis (WNE) Treatment & Management

Updated: Apr 05, 2021
  • Author: David J Cennimo, MD, FAAP, FACP, FIDSA, AAHIVS; Chief Editor: Michael Stuart Bronze, MD  more...
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Approach Considerations

Treatment of West Nile encephalitis (WNE) consists of prevention, followed then by supportive care. The mainstay of prevention is limiting personal mosquito-bite exposure. Mosquito netting and barrier protection are most helpful and may be augmented by mosquito repellents.

Initially, it is important to exclude herpes simplex virus (HSV) encephalitis among the differential diagnoses, as this is the only viral encephalitis for which there is a treatment, and prompt intervention will likely be beneficial to the patient.

Supportive care focuses on minimizing the potential for cerebral edema by electrolyte flux of fluid shift in patients with WNE.

No proven benefit has been observed in small numbers of patients treated with interferon, ribavirin, or intravenous immunoglobulin (IVIG).

Consultation with an infectious disease specialist and a neurologist should be considered. A repeat lumbar puncture is usually unnecessary. Further outpatient care is usually unnecessary; however, follow-up and rehabilitation of neurologic deficits will likely be beneficial.



Avoidance of mosquito exposure, particularly around dawn and dusk, may help mitigate the risk of exposure to West Nile virus (WNV). Mosquito repellents, such as DEET, as well as barrier netting, are helpful. Mosquito-control programs are also able to reduce rates of human infection and are typically employed when surveillance identifies increased local risk. A 2005 study found that the odds of infection were 6-fold higher in untreated areas than in areas treated with aerosolized pyrethrin spraying. [31] Routine local control, such as limiting stagnant areas of water collection, may also be beneficial.

No vaccine is currently FDA-approved for WNV, although studies of live attenuated vaccines are ongoing (up to phase II clinical trials), which have shown safety and tolerability, as well as immunogenicity. [32, 33]  No clinical trials for WNV vaccine are in phase III.