The local health officer or his designee shall appoint such personnel as may be necessary to administer the public health services within the county or district. Upon the request of such local health officer or his designee, the State Personnel Department shall establish a local register of eligibles who are residents of the county or district in which the vacancy exists or who are employed by the county health department or district health department in the county or district in which the vacancy exists. If no appointment is made from the local register or there is no local register, an appointment shall be made from the statewide register; provided, that on July 1, 1975, any person employed in county or district health departments under provisions of the Merit System council for county departments of health shall be covered under the provisions of the state Merit System Act with the same status.