They are extremely difficult to dislodge and hard to exterminate in buildings where there are large quantities of beds, like a dormitory or apartment buildings. While these bed bugs do not transmit diseases, they do leave bites that can cause painful irritation and itching. Protect Your Bed With A Bed Bug Mattress Protector Bed Bug Mattress Protector A bed bug mattress protector is an encasement that will seal off your mattress completely and are usually impermeable to dust mites, bed bugs, mold and bacteria. They help to keep existing bed bugs trap within the encasement and prevent new ones from burrowing into the mattress where they reproduce, live and feed on their host. These mattress covers should be left on the bed for at least twelve to eighteen months, because bed bugs can survive for up to a year and a half without feeding.