RIDGE MANOR — Hernando County health officials are warning the public to be vigilant about mosquito bites after a sentinel chicken tested positive this week for Eastern equine encephalitis, a mosquito-borne virus that can be deadly in humans and horses. The Hernando Health Department said Friday that the chicken was part of a flock at the county's East Hernando Transfer Station, near State Road 50 and Ridge Manor Boulevard. The positive test result means that mosquitoes carrying the virus are present in the area. Eastern equine encephalitis is a rare disease that can cause inflammation of the brain. Symptoms include a sudden headache, high fever, chills and vomiting. Hernando County has never had a human case of the disease. Residents are urged to drain standing water and protect themselves from bites by covering up, using repellent and avoiding the outdoors at dusk and dawn, when mosquitoes are most active.