(WASHINGTON) -- New research sheds light on Morgellons disease, a controversial condition marked by crawling sensations in the skin.
In response to increasing reports of Morgellons symptoms, scientists from the U.S. Centers for Disease Control and Prevention (CDC) analyzed blood and skin samples from 115 patients in Northern California and found no evidence linking Morgellons to an infection or environmental cause.
"We saw a growing number of people complaining about these unusual symptoms, and as a public health agency we felt the need to see what was going on," said CDC spokesman Daniel Rutz. "It was important to rule out an infectious cause because a lot of people were concerned about transmission."
The study was published Wednesday in the journal PLoS One.
Morgellons is not an official diagnosis. Rather, it's a collection of unexplained symptoms including abnormal sensations that sufferers describe as the feeling of insects crawling on the skin. Symptoms also include fatigue.
And, perhaps most peculiarly, one symptom is tiny fibers found embedded in waxy scabs on the skin.
"They're not alive," said Rutz, referring to rumors circulating on Morgellons message boards that the fibers are insects -- or even alien matter. "They're pieces of cotton and other elements of clothing; common debris."
Roughly 40 percent of the skin samples showed signs of chronic irritation.
"These sores appear often to be the result of people picking at themselves, as they would if they had a chronic irritation that couldn't be resolved any other way," said Rutz, adding that fibers likely slough off clothes and become encrusted in the healing wounds.
The study uncovered some other common threads: Drugs were detected in hair samples from half of the patients; and more than one-third of patients had a neuropsychiatric condition.
Dr. Anne Louise Oaklander, a neurologist at Massachusetts General Hospital in Boston, said Morgellons might stem from damage to the nerves that transmit the itch sensation.
"This causes them to fire without appropriate cause, and it's natural that people interpret this as a sensation of insects crawling on the skin," she said.
Oaklander said the CDC study ruled out the possibility of insects or infections in Morgellons, opening the door for research into nerve damage and possible treatments.
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