When Joni Mitchell was admitted to the hospital this week after being found unconscious in her Los Angeles home, a controversial affliction she has long suffered with hit the headlines again.

The 71-year-old singer-songwriter has often complained of her battle with Morgellons, a medical mystery that has stumped the scientific community for years.

"I couldn't wear clothing. I couldn't leave my house for several years," she described in her 2014 book Joni Mitchell: In Her Own Words. "Sometimes it got so I'd have to crawl across the floor. My legs would cramp up, just like a polio spasm. It hit all of the places where I had polio." (It's unclear if Morgellons was related to her recent hospitalization, but she has certainly brought attention to the issue over the years.)

Morgellons involves unexplained itching sensations



Sufferers of Morgellons report itching, biting, and crawling sensations. "Fibers in a variety of colors protrude out of my skin," Mitchell has said. "They cannot be forensically identified as animal, vegetable or mineral."



They say their skin feels like it's erupting from underneath, infested by insects, worms, or mysterious fibers. Like Mitchell, they say their symptoms are debilitating: they point to lesions that won't heal, and say the biting and stinging that afflicts them every day leaves them fatigued and depressed, even affecting their memory.



"[it's] as if you're being bitten by fleas and lice" Mitchell wrote in her book: "Morgellons is constantly morphing. There are times when it's directly attacking the nervous system, as if you're being bitten by fleas and lice. It's all in the tissue and it's not a hallucination. It was eating me alive, sucking the juices out. I've been sick all my life."

The condition was first described in the 1600s, and then named in 2001 by an American, Mary Leitao, whose son's itching couldn't be remedied or explained by modern medicine. Leitao eventually scraped his skin and examined the samples under a microscope. She found fiber-like strands, which she determined "cannot be coming out of my son's body," she told the Pittsburgh Post-Gazette.



After getting frustrated by her doctors' dismissive tones, she launched the Morgellons Research Foundation and began pressuring Congress to figure out what was going on. The movement gained traction in the United States in 2005, when lawmakers requested that the Centers for Disease Control and Prevention investigate.

Researchers say Morgellons is a "mass-shared delusion"

For the past decade, researchers have searched for a biological cause or single underlying factor that might explain the suffering. But they have mostly concluded that Morgellons is "a psychosis or mass-shared delusion."

In one of the most comprehensive studies to date, published in the journal PLOS, researchers from the CDC collected detailed epidemiological information, medical histories, and skin samples from 115 Morgellons sufferers in Northern California.

"No parasites or mycobacteria were detected," they reported. The researchers also couldn't find any environmental explanation for patients' suffering.

The fiber-like strands on sufferers were mostly just cotton debris, probably lint from clothing. Their skin damage seemed to be caused by nothing more than sun exposure. While some patients had sores, these appeared to have arisen from chronic picking and scratching.

Interestingly, a large number of people in the study had a psychiatric or addictive condition, including depression and drug use. Among half of the participants in the study used drugs, but it wasn't clear whether the drugs caused the symptoms or whether they were being used to deal with the disease.



Even so, the researchers could not uncover any particular underlying medical condition or infectious source, and concluded that Morgellons is "similar to more commonly recognized conditions such as delusional infestation."

That last conclusion is echoed by other research on Morgellons patients. One study, out of the Mayo Clinic, concluded this way: "Although patients are convinced that their skin is infested with parasites or inanimate material," skin biopsies and specimen analyses turned up no evidence of infestation. The patients were probably suffering from delusional parasitosis — or the false belief that one is infected with parasites — the researchers determined.

Some more recent research suggests Morgellons may belong in the same family as tick-borne illnesses like Lyme disease — but this is a relatively new theory and the link hasn't been confirmed by multiple studies.



Still, many patients insist Morgellons is very real

For now, delusional parasitosis is the most common diagnosis for Morgellons sufferers, with many skeptics arguing that this is just "a cultural entity spreading mainly on the internet." (There are a few medical experts who think Morgellons is a real disease, but they are in the minority.)

Doctors, for their part, seem exasperated by the phenomenon. As Jeffrey Meffert, a dermatologist at the University of Texas Health Science Center in San Antonio, told Newsweek, "People with delusional parasitosis are very functional and rational except when it comes to this one issue." He continued: "Many dermatologists would rather these patients never show up, because they don't feel they have the time to spend. No one knows how to deal with them."

The exposure that's created by celebrities can help shape the research agenda

Still, the issue hasn't gone away. For people like Mitchell, the lack of empirical evidence doesn't diminish their suffering. They feel dismissed by most doctors and let down by modern medicine. And even though many experts feel that further research is a waste of time and money, calls to pursue the issue are unlikely to disappear.



Indeed, the online discussion — fueled by celebrities like Mitchell — "gives the condition a name, gives it a shape, and gives the sufferers a community with which to interact and legitimize the condition" said Tim Caulfield, a researcher and author of Is Gwyneth Paltrow Wrong About Everything? When Celebrity Culture and Science Clash.



That community creates advocacy, and winds up driving the research agenda, whether or not it's scientifically warranted. "The exposure that's created by celebrities," Caulfield continued, "can help shape the research agenda, and researchers are very savvy. As things gain exposure in popular culture, it creates an interest in the area, and perhaps increases the chance for research funding. The Joni phenomenon is part of this."

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