53 Pa. Stat. § 24664
Upon receipt by the bureau of health of a report of the existence of a case of cholera, smallpox (variola or varioloid), scarlet fever, typhus fever, yellow fever, relapsing fever, diphtheria, diphtheritic croup, membraneous croup, or leprosy, in said city, it may at once place, or cause to be placed, in a conspicuous place or places upon or near the house or premises in which said case may be located, a placard or placards upon which shall be printed in large letters the name of the disease from which the person or persons in said house or premises may be suffering as aforesaid, as the case may be: Provided, That variola or varioloid shall be placarded as "smallpox," and that diphtheritic croup and membraneous croup shall be placarded as "diphtheria," and said placard or placards shall remain thereon until such time as the rules and regulations established by the said bureau of health regarding the destruction or disinfection of infected bedding, clothing or other articles which have been exposed to infection, and the disinfection of houses and premises shall have been fully complied with: Provided, That in addition to the placarding aforesaid, or in lieu of the same, the said bureau of health may place a guard or guards upon said house or premises.
53 P.S. § 24664