Yes, they’re not all sex based. See also Morgellons:
Morgellons (/mɔːrˈɡɛlənz/) is the informal name of a self-diagnosed, unconfirmed skin condition in which individuals have sores that they believe contain some kind of fibers. Morgellons is poorly characterized but the general medical consensus is that it is a form of delusional parasitosis; the sores are the result of compulsive scratching, and the fibers, when analysed, turn out to originate from textiles....
People usually self-diagnose Morgellons based on information from the Internet and find support and confirmation in online communities of people with similar illness beliefs. In 2006, Waddell and Burke reported the influence of the Internet on people self-diagnosed of Morgellons: "physicians are becoming more and more challenged by the many persons who attempt self-diagnosis on-line. In many cases, these attempts are well-intentioned, yet wrong, and a person's belief in some of these oftentimes unscientific sites online may preclude their trust in the evidence-based approaches and treatment recommendations of their physician." Dermatologist Caroline Koblenzer specifically faults the Morgellons Research Foundation (MRF) website for misleading people: "Clearly, as more and more of our patients discover this site (MRF), there will be an ever greater waste of valuable time and resources on fruitless research into fibers, fluffs, irrelevant bacteria, and innocuous worms and insects."Vila-Rodriguez states that the Internet promotes the spreading and supporting of "bizarre" disease beliefs, because "a belief is not considered delusional if it is accepted by other members of an individual’s culture or subculture".
The Los Angeles Times, in an article on Morgellons, notes that "[t]he recent upsurge in symptoms can be traced directly to the Internet, following the naming of the disease by Mary Leitao, a Pennsylvania mother". Robert Bartholomew, a sociologist who has studied the Morgellons phenomenon, states that the "World Wide Web has become the incubator for mass delusion and it (Morgellons) seems to be a socially transmitted disease over the Internet." According to this hypothesis, people with delusions of parasitosis and other psychological disorders become convinced they have "Morgellons" after reading Internet accounts of others with similar symptoms. This is known as mass psychogenic illness, where physical symptoms without an organic cause spread to multiple people within the same community or social group. A 2005 Popular Mechanics article stated that Morgellons symptoms are well-known and characterized in the context of other disorders, and that "widespread reports of the strange fibers date back" only a few years to when the MRF first described them on the Internet.
The Dallas Observer writes that Morgellons may be memetically spread via the Internet and mass media, and "[i]f this is the case, then Morgellons is one in a long line of weird diseases that have swept through populations, only to disappear without a trace once public concern subsides". The article draws parallels to several media-spread mass delusions.
In 2008, The Washington Post reported that Internet discussions about Morgellons include many conspiracy theories about the cause, including biological warfare, nanotechnology, chemtrails and extraterrestrial life. The Atlantic says it "even received pop-culture attention" when it was featured on Criminal Minds, adding that some people have linked Morgellons "to another illness viewed skeptically by most doctors, chronic Lyme disease".
en.m.wikipedia.org/wiki/Morgellons