Whenever the director of health notifies the occupant or occupants of a business building that there is evidence of rat infestation of the building, such occupant or occupants shall immediately institute appropriate measures for freeing the premises each occupies of all rats, and that unless suitable measures for freeing the building of rats are instituted within fifteen (15) days after receipt of notice and unless continuously maintained in a satisfactory manner until the building is free of rats, the director of health is authorized and directed to free the building of rats at the expense of the owner thereof, and the director of health shall submit bills for the costs thereof to the owner or occupant of the building, and if the same are not paid, the director of health shall certify the amount due from the owner or occupant to the city attorney, and the city attorney shall bring suit to collect the same. (Prior code § 18-22-6)