LAS VEGAS (AP) _ The Southern Nevada Health District is warning Clark County residents that mosquitoes have tested positive for West Nile virus in eight area ZIP codes.

The Las Vegas Sun reports ( ) that there have been no reported human cases of the virus in Clark County this year.

Health records show two people were infected last year. No deaths were reported.

Health officials suspect mosquitoes infected with the West Nile virus may be present throughout the Las Vegas Valley. They encourage residents to use insect repellants, wear protective clothing and limit outdoor activity at dusk and dawn when mosquitoes are most active.

The mosquito-carried virus can cause symptoms such as fever, fatigue, aches and rash.