Section 78A. The trustees of a county tuberculosis hospital may admit as patients in said hospital persons who are suffering from chronic disease; provided, that sufficient beds are at all times available for persons with tuberculosis who are eligible for admission to said hospital; and provided, further, that before the trustees admit any such chronic disease patients, said hospital is inspected by the department, is duly licensed under section seventy-one, and otherwise complies with sections seventy-two and seventy-three. Such trustees shall promulgate rules and regulations concerning the admission of such chronic disease patients as well as the method of reimbursement and the charges for their care and treatment, notwithstanding any contrary provision of this chapter. The charges to the general public for all general health supplies, care, services and accommodations shall be the rate or rates established by the executive office of health and human services or a governmental unit designated by the executive office. Such rules and regulations shall be approved by the department before taking effect.