West Nile encephalitis.

After the New York outbreak of West Nile Virus encephalitis in the summer of 1999, awareness that vulnerable children and adolescents may be at risk for this mosquito-borne viral infection intensified. The Nurse Practitioner can play an invaluable critical role to recognize and diagnose this arthropod-borne virus. Pathophysiology, vector transmission, clinical manifestations and laboratory findings are discussed in this article. Emphasis is placed on the PNP's role of providing anticipatory guidance concerning prevention of outbreaks and physical management that focuses on the elimination of mosquito-breeding areas, reducing personal exposure, and biological control of mosquito populations.