District health officials also announced that another resident is hospitalized with the virus.
Maryland health officials reported the state's first death from the virus last week. No deaths have been reported in Virginia.
Federal officials say cases nationwide are up sharply and may rival the record years of 2002 and 2003. Officials say an early spring and hot summer may be responsible. Mosquitoes get the virus from feeding on infected birds and then spread it to people they bite.
Officials say that nearly 80 percent of people infected with West Nile virus will not become ill, but that roughly one in 150 people infected develop severe infection such as encephalitis or meningitis.
Symptoms of severe West Nile virus infection include headache, high fever, stiff neck, and/or tremors and muscle weakness. The elderly and those with weakened immune systems are most at risk.
The Associated Press contributed to this report