What are the Signs and Symptoms of WNV?
WNV affects the nervous system. However, symptoms vary:
Serious symptoms in a few people.
Less than one percent of individuals (about 1 in 150 people) infected with WNV will develop severe illness. The severe symptoms can include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. These symptoms may last several weeks and neurological effects may be permanent. WNV can be fatal.
Milder symptoms in some people.
Up to 20 percent of the people (about 1 in 5) who become infected will display symptoms which can include fever, headache, body aches, nausea, vomiting and sometimes swollen lymph glands or a skin rash on the chest, stomach and back. Symptoms generally last for just a few days, although even previously healthy people have been sick for several weeks.
No symptoms in most people.
Approximately 80 percent of people (about 4 out of 5) who are infected with WNV will not show any symptoms.
People over the age of 50 have a higher chance of getting sick and are more likely to develop serious symptoms when infected with WNV.