New human cases of West Nile virus have been confirmed in Cleburne, Miller, Pulaski and Sevier counties. The state has a total of ten human cases of the mosquito-borne virus -- six in Jefferson County and one each in the newly-announced counties. Also, a bird was found with the disease in Washington County. The state is in its peak period for transmission of the disease, which is a particular danger to older people. Most people who contract the disease have mild symptoms or no symptoms. In rare cases, the illness can bring on fatal brain swelling. The ordinary symptoms include fever, muscle and joint aches and listlessness. The virus cannot be passed from human to human. The Health Department says the peak time for humans to contract the disease in Arkansas runs through September 21st.