West Nile Encephalitis:
        This viral disease is now well established in the eastern half of the US. It is rare even in areas
with high outbreaks. Mortality is highest in patients older than age 75. The majority of infected
patients will either have no symptoms or very mild ones. Incubation period is two weeks. When
symptoms do occur, they include: fever, weakness, nausea, vomiting, headache, altered mental
state, decreased reflexes, stiff neck and rash. Paralysis occurs in 10% of patients with symptomatic
encephalitis. A blood test is available to detect the disease. Treatment is with intravenous antivirals.
        Prevention is with avoidance of mosquitoes and use of repellents. Avoid repellents in children
under two years of age.