infectious diseases
West Nile Virus
Symptoms and Signs of West Nile Virus
Most (4 out of 5) patients with West Nile virus infection have no symptoms. About 1 in 5 develop fever along with other symptoms such as headache, body aches, joint pain, vomiting, diarrhea, or rash. About 1 in 150 patients develop severe central nervous system involvement with Encephalitis , Acute flaccid paralysis may occur that is usually clinically and pathologically identical to that in Poliomyelitis , with damage of anterior horn cells. West Nile virus acute flaccid paralysis can occur without fever or apparent viral prodrome and often presents as isolated limb paresis or paralysis and may progress to respiratory paralysis requiring mechanical ventilation. Most people with typical fever and myalgia recover completely, but fatigue and weakness can last for weeks or months. Patients who recover from West Nile virus encephalitis or acute flaccid paralysis often have residual neurologic deficits. 