(CBS/AP) What if it felt like there were tiny bugs crawling all over your body, causing oozing sores and mysterious fibers sprouting from your skin? That's how many people described their symptoms to government doctors several years ago, with health officials sometimes receiving up to 20 calls a day from sufferers.
Many of these people lived in California, prompting one of that state's U.S. senators, Dianne Feinstein, to ask for a scientific study. In 2008, federal health officials began to study people who said they were affected by this freakish condition called Morgellons disease - named from a 1674 medical paper that described similar symptoms.
What did the long-awaited study conclude? Morgellons exists only in the patients' minds.
Sufferers of Morgellons describe symptoms including fatigue, erupting sores, crawling sensations on their skin, and mysterious red, blue or black fibers sprouting from their skin. Some say they've suffered for decades.
The study, published Jan. 25 in the journal PLoS One, cost nearly $600,000. It focused on more than 3 million people who lived in 13 counties in Northern California. After researchers went through Kaiser Permanente patient records, they flagged 115 people who had what sounded like Morgellons. That's the equivalent of roughly 4 out of every 100,000 Kaiser enrollees. "So it's rare," said Mark Eberhard, a Centers for Disease Control and Prevention official who was part of the 15-member study team. But when the researchers dug further to find a cause for the disease, they came up empty.
"We found no infectious cause," Eberhard said.
Most of the afflicted patients were middle-aged white women. One hundred of the patients agreed to answer survey questions and 40 consented to physical and psychological tests. The patients had no diseases, but more depression than the general public and were more obsessive about physical ailments, the study found.
Afflicted patients have documented their suffering on websites and many have vainly searched for a doctor who believed them. Some doctors believe the condition is a form of delusional parasitosis, a psychosis in which people believe they are infected with parasites.
Last May, Mayo Clinic researchers publishedand found none of them suffered from any unusual physical ailment, HealthPop reported. The study concluded that the sores on many of them were caused by their own scratching and picking at their skin.
Even though no explanation was found, study author Felicia Goldstein, an Emory University neurology professor, said the "absence of evidence is not evidence of absence."
She said perhaps the patients could be helped by cognitive behavioral therapy that might help them deal with possible contributing psychological issues.
The Mayo Clinic has more on managing Morgellons disease.