Iowa Code § 137.111

Upon establishment of a district board, the district board shall designate a treasurer to serve as treasurer of the district health department, and shall designate an auditor to serve as auditor of the district health department. A treasurer or auditor of any county within the district may also serve in the capacity of treasurer or auditor of the district health department, respectively, or the district board may contract with a third party to act as the treasurer or auditor of the district health department. A county treasurer’s or county auditor’s official bond may extend to cover their respective duties performed on behalf of the district health department.