Section 43A. Every officer or employee of a county required to furnish a fidelity bond with a surety or sureties shall furnish a bond with a surety company authorized to transact business in the commonwealth, as surety. Unless otherwise provided by law, every such bond shall be approved as to form by the superior court, which may require to be included in such bond such terms, provisions and conditions as, in its opinion, will carry into effect the intent of the law requiring the giving of such bond. The premium on such bond shall in every case, except in the case of the treasurer of Suffolk or Nantucket county, be paid by the county.