In the event a vacancy occurs in the office of members of the county board of education, the vacancy shall be filled by appointment by a majority of the remaining members of the county board of education, and the appointee shall hold for the unexpired term. In the event the vacancy is not filled by the remaining members of the county board within 30 days, the State Superintendent of Education shall fill such vacancy by appointment. The county superintendent of education shall notify the State Superintendent of Education when a vacancy in the office of a member of the county board of education has not been filled within 30 days.