Articles relating to delusional parasitosis, a mental disorder in which individuals have a persistent belief that they are infested with living or nonliving pathogens such as parasites, insects, or bugs, when no such infestation is present. They usually report tactile hallucinations known as formication, a sensation resembling insects crawling on or under the skin. Morgellons is considered to be a self-diagnosed subtype of this condition, in which individuals have sores that they believe contain harmful fibers.