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There is no specific treatment for West Nile virus infection at this time. Intensive supportive therapy is directed toward the complications of brain infection. Anti-inflammatory medications, intravenous fluids, and intensive medical monitoring may be required in severe cases. In milder cases, over-the-counter (OTC) pain relievers such as ibuprofen (Advil, Motrin) or aspirin may help reduce symptoms of pain and fever. There is no specific antibiotic or antiviral for the viral infection. There is no vaccine to prevent the virus.
Mild or symptom-free infections are common with the West Nile virus. Among all people who become infected, only two out of 10 develop any symptoms. Of those, most only have mild symptoms similar to those of the flu, such as headache, body aches, joint pain, swollen lymph nodes, vomiting, diarrhea, or rash. The symptoms are not severe enough for most people to seek medical care, but tiredness and weakness can last for several weeks. Typically, only one in 150 infections lead to severe or neuroinvasive (nervous system disease) infections, according to the CDC. Neuroinvasive disease is caused by infection and inflammation of the surface covering of the brain (meningitis) or deeper infection of the brain itself (encephalitis).
Neuroinvasive disease is uncommon but more likely to occur in those over age 50. There are two general symptoms of neuroinvasive disease. Meningitis is marked by headache, high fever, and neck stiffness. Encephalitis causes these symptoms but may progress to stupor (sleepiness), disorientation, hallucinations, paralysis, coma, tremors, convulsions, and rarely death. Sometimes general weakness progressing to complete paralysis occurs, similar to polio; this is called acute flaccid paralysis.
West Nile virus can have some long-term effects after severe illnesses. West Nile virus meningitis or encephalitis may result in a prolonged recuperation and rehabilitation period, especially in the elderly. Memory loss, depression, irritability, and confusion are the most prevalent residual effects.
Since most cases of West Nile virus infection are mild, the prognosis for recovery is generally good. In severe cases, death rates are highest in the elderly.
For more information, read our full medical article on West Nile virus.
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