§ 225-b. Contracts for visiting nursing services. The board of supervisors of any county may, upon recommendation of the county board of health, contract with any nonprofit institution or agency, wholly or partly under private control, organized to furnish visiting nursing and public health services and agree to pay fees specified in the said contract for such services furnished to inhabitants of the county. Any fees for services collected by the institution or agency for services rendered under such contract shall be credited against the amount payable by the county under the terms of the contract. Such contracts shall be effective only upon approval of the state commissioner of health and the state comptroller. Such contracts shall provide that the contracting institution or agency will comply with all rules promulgated by the county health commissioner. Such boards of supervisors are authorized and empowered to appropriate the sums required to be paid to such institutions and agencies under the terms of such contracts and to raise the amount thereof by taxation.