More on Arboviruses. Although periodic epidemics have occurred only in the Midwest and Southeast, SLE virus is distributed throughout the lower continental United States. During epidemics, people over 60 are 5 to 40 times more likely to be symptomatic than those under 10 years of age. When they do develop, symptoms usually start between 5 and 20 days after exposure. Encephalitis is an inflamation of the brain that can drastically affect motor skills and cause permanent damage if not treated quickly.
Symptoms range from mild headaches to coma and death.
Other symptoms include fever, nausea, stiff neck and back, light sensitivity, confusion, drowsiness, irritability, and motor skill impairment. After invasion of the central nervous system the virus is thought to follow initial virus replication in peripheral sites and a period of viremia. Clinically, it is essential to distinguish the arboviral encephalitides from two viral ones that are potentially deadly, but treatable. These are herpes simplex encephalitis, and the less common varicella-zoster encephalitis, which is deadly in patients with immunological deficiencies. We know, however, that wild bird populations are central to the transmission cycle.