For the purposes of this act, necessary absence from the city, illness or other temporary disability shall continue for fifteen consecutive days before the deputy mayor shall be empowered to assume the duties of office of mayor, subject however, to the provision that in the event that there shall be before the mayor an ordinance or resolution, for approval or disapproval, and that said mayor, by reason of his illness, is unable to act within the period allowed by law, then and in that event, the deputy mayor shall assume the duties of the office of mayor upon the filing with the city clerk, by the mayor's attending physician, of a statement in writing that the mayor is unable to perform the duties of his office.
53 P.S. § 30356