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West Nile Virus Symptoms

May contain: animal, insect, invertebrate, mosquito, and spider

Call your health care provider if you have questions about the symptoms associated with West Nile virus.  Symptoms of West Nile Virus may vary:    

  • Serious Symptoms in a few people.  Less than one percent of individuals  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 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 who are infected with WNV will not show any symptoms.      

For more information regarding the symptoms of West Nile Virus you may find these links helpful: