The county commissions of the several counties of this state, both within and outside such counties, except in counties of the third or fourth classification (other than the county in which the hospital is located) where there already exists a hospital organized pursuant to chapters 96, 205 or 206; provided, however, that this exception shall not prohibit the continuation of existing activities otherwise allowed by law, are hereby authorized, as provided in sections 205.160 to 205.340, to establish, construct, equip, improve, extend, repair and maintain public hospitals and engage in health care activities, and may issue bonds therefor as authorized by the general law governing the incurring of indebtedness by counties.