New cases of the mosquito-borne illness Eastern Equine Encephalitis have led the state health department to expand aerial mosquito spraying on Thursday.

Six additional horses were diagnosed with the virus bringing the total statewide to 28 cases in 11-counties. Livingston County is the latest county to be added to the list for treatment.

Areas slated for treatment last night (Thursday) from dusk to dawn, weather and time  permitting were Barry County including Hastings, Kent, Newaygo, Oceana, Muskegon, Mecosta, Ionia and Jackson Counties.