The symptoms of West Nile virus include fever, headache, body aches, joint pain, vomiting, diarrhea and rash. These symptoms affect around 1 in 5 people; most people won't develop symptoms. However, a small percentage - less than 1 percent - can develop a serious neurological disease such as encephalitis or meningitis. Symptoms appear three to 14 days after being bitten.
Medical News Today