(b) (1) A tenant shall promptly notify a landlord orally or in writing when the tenant knows or reasonably suspects that the tenant's dwelling unit is infested with bed bugs. Not later than five business days after receiving such notice, the landlord shall inspect or obtain an inspection by a qualified inspector of the dwelling unit and any contiguous unit of which the landlord is an owner, lessor or sublessor, and may enter any such dwelling unit or contiguous unit for the purpose of conducting such inspection as provided in subparagraph (A) of subdivision (2) of this subsection. If the landlord conducts the inspection, the landlord must provide written notice to the tenant within two days indicating whether or not the unit is infested with bed bugs. The notice shall inform the tenant that, if the tenant is still concerned that the unit is infested with bed bugs, the tenant may contact the local health department and shall provide relevant contact information on said notice. If the inspection determines that any such dwelling unit or contiguous unit is infested with bed bugs, the landlord shall, not later than five business days after the date of the inspection, take reasonable measures, as determined by such qualified inspector, to effectively treat the bed bug infestation, including treating or retaining the services of a pest control agent to treat the dwelling unit and any contiguous unit of which the landlord is an owner, lessor or sublessor, except the landlord may first attempt to effectively treat such infestation. If the landlord treats such bed bug infestation without retaining the services of a pest control agent, the landlord shall first vacuum the areas to be treated and shall, not later than five business days after the date of such treatment, obtain an