JACKSONVILLE, Fla.—A human case of West Nile virus has been confirmed in Duval County and there is a concern it could spread to others, the Department of Health announced Thursday.

There is a risk of further transmission to humans of the mosquito-borne illness, says a release from the Florida Department of Health in Duval County.

Health officials remind residents and visitors to Duval County to avoid being bitten by mosquitoes by taking basic precautions to limit exposure.

The health department refuses to say where the person contracted the illness.

City of Jacksonville Mosquito Control officials are continuing surveillance and prevention efforts in the county.

Officials ask residents to 'drain and cover,' meaning drain all standing water and cover yourself with clothing/repellant.

Those who've contracted the disease may have febrile illness, encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord), the Centers for Disease Control and Prevention say.

This is the first case of West Nile reported in the state of Florida this year and one of at least 302 nationwide. Seven people have died this year of the disease, according to CDC statistics.

The first case of West Nile was reported in the U.S. in 1999 in New York and has slowly spread throughout the continental United States. From '99 to 2015, 43,937 people have contracted the disease and 1,911 have died. West Nile virus has a 4 percent mortality rate, the CDC says.

This is a developing story. Stay with First Coast News for updates.