Morgellons () is the informal name of a self-diagnosed, scientifically unsubstantiated skin condition. Individuals claiming to have Morgellons typically exhibit sores, which they believe “contain” some sort of fibrous material. Morgellons is poorly characterized, but the general medical consensus is that it is a form of delusional parasitosis. The sores are typically the result of compulsive scratching, and the fibers, when analysed, were consistently found to have originated from clothings and other textiles.
Mary Leitao, a mother who rejected the medical diagnosis of her son's delusional parasitosis, named the supposed disease in 2002. She revived it from a letter written by a physician in the mid-17th century. Leitao and others involved in her Morgellons Research Foundation successfully lobbied members of the U.S. Congress and the U.S. Centers for Disease Control and Prevention (CDC) to investigate the condition in 2006. CDC researchers issued the results of their multi-year study in January 2012, indicating that no disease organisms were present in people with so-called "Morgellons", that the fibers were likely cotton, and concluded that the condition was "similar to more commonly recognized conditions such as delusional infestation".