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Teen girls' mystery illness now has a diagnosis: mass hysteria

The day after TODAY reported on the baffling case of 12 teenage girls at one school who mysteriously fell ill with Tourette's-like symptoms of tics and verbal outbursts, a doctor who is treating some of the girls has come forward to offer an explanation. Dr. Laszlo Mechtler, a neurologist in Amherst, N.Y., says the diagnosis is "conversion disorder," or mass hysteria.

"It's happened before, all around the world, in different parts of the world. It's a rare phenomena. Physicians are intrigued by it," Mechtler told TODAY on Wednesday. "The bottom line is these teenagers will get better."

On the show Tuesday, psychologist and TODAY contributor Dr. Gail Saltz noted that just because the girls' symptoms may be psychological in origin doesn't make them any less real or painful.

“That’s not faking it. They’re real symptoms,” Saltz continued. “They need a psychiatric or psychological treatment. Treatment does work.’’

Conversion disorder symptoms usually occur after a stress event, although a patient can be more at risk if also suffering from an illness. Symptoms may last for days or weeks and can include blindness, inability to speak, numbness or other neurologic problems.

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It's unclear which of the girls first showed symptoms, or whether any particular event triggered the outbreak. High school cheerleader and art student Thera Sanchez says her tics, stammer and verbal outbursts appeared out of the blue after a nap one day last October.

“I was fine. I was perfectly fine. There was nothing going on, and then I just woke up, and that’s when the stuttering started,” Sanchez told TODAY.

“I’m very angry,’’ Sanchez told TODAY’s Ann Curry during an interview Tuesday. “I’m very frustrated. No one’s giving me answers.’’

The New York State Health Department has been investigating the case for more than three months and says the school building is not to blame. Officials from the LeRoy Junior-Senior High School in upstate New York, where all the girls attended when their symptoms began, have released environmental reports, conducted by an outside agency, showing no substances in any of the school buildings that could cause health problems.

Health officials ruled out carbon monoxide, illegal drugs and other factors as potential causes. Officials say no one at the school is in any danger.

“We have conclusively ruled out any form of infection or communicable disease and there’s no evidence of any environmental factor,’’ Dr. Gregory Young of the New York Department of Health told NBC News.

Related: Click here to read the school district's statement and full environmental reports

But some of the girls' parents say they're not satisfied with the explanations so far.

"Obviously we are all not just accepting that this is a stress thing," Jim Dupont, father of one of the affected girls, told TODAY on Wednesday. "It's heart wrenching, you fear your daughter's not going to have a normal life."

Read the original story: Girls' medical mystery baffles doctors

Scott Stump, Rebecca Dube and NBC News contributed to this report.

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