; or (ii) the date described in clause (ii) or (iii) of subparagraph (A). (4) Renewals (A) In general A public health emergency declared under paragraph (1) (or any renewal thereof), may be renewed only if— (i) the Secretary publishes in the Federal Register and transmits to Congress a declaration renewing the emergency (or the most recent renewal); and (ii) there is enacted into law a joint resolution renewing the emergency pursuant to subsection (j). (B) No renewal if already terminated A public health emergency declared under paragraph (1) may not be renewed if such emergency has already terminated under paragraph (3). (C) Substantially similar declarations Any declaration under paragraph (1) that is based on circumstances stemming from a nexus of facts or events that is substantially similar to that on which an earlier declaration under such paragraph was issued shall be treated as a renewal of the earlier declaration for purposes of this section. (5) Effect of termination (A) In general Effective on the date of the termination of a public health emergency under paragraph (3)— (i) except as provided by subparagraph (B), any authorities exercised by reason of the emergency shall cease to be exercised; (ii) any amounts reprogrammed or transferred under any provision of law with respect to the emergency that remain unobligated on that date shall be returned and made available for the purpose for which such amounts were appropriated; and (iii) any contracts entered into under any provision of law for construction relating to the emergency shall be terminated unless construction commenced under the contract before that date. (B) Savings provision Except as specifically provided in subparagraph (A), the termination of a public health emergency shall not affect— (i) any action taken or proceeding pending not finally concluded or determined on the date of the termination under paragraph (3); (ii) any action or proceeding based on any act committed prior to that date