A 66-year-old man and a 50-year-old woman have become the 27th and 28th confirmed cases of West Nile virus in Duval County in 2012, according to the Duval County Health Department. There has also been one reported death associated with a confirmed case of the mosquito-borne illness in the county. About one in 150 people infected with the virus will develop severe illness, with symptoms including high fever, headache and muscle weakness. Symptoms may last several weeks and neurological effects may be permanent, according to the Health Department. The public should drain standing water to stop mosquitoes from multiplying, cover skin with clothing or repellent and cover doors and windows.