Transcript for Mysterious Outbreak at N.Y. School?
We have more now on that mysterious outbreak of two -- like symptoms among a group of high school students most of them girls in upstate New York. Health officials -- a case of mass hysteria but they haven't convinced some parents and investigators like Erin Brockovich who suspect toxic waste is the -- We -- neglected to the girl suffering from the symptoms and their moms in just a moment but first ABC's -- Davis has the latest on the controversy. Months of mounting frustrations surrounding -- medical mystery and -- New York are now coming to a head. And I'm not. You yet you'll need to do not. Nearly two dozen people including a 36 year old are now experiencing uncontrollable tics seizures and outbursts. Today this. This is a good day and this what you see this is a good day. State environmental activist Erin Brockovich suspects these two arrests like symptoms could be environmental. But after testing the water and a year the new York state department of health issued a report saying no infectious or environmental ideologies were found. And at least eight of the girls have been diagnosed with conversion disorder where stress manifests in real physical symptoms this is obviously not -- And this is a constellation of multiple symptoms of which wanna. Of which just this can be -- The doctors did say they notice that after some of the -- appeared on TV showing one particular kind of -- others would start to take in similar manners. One Doctor Who hasn't treated the -- even recently suggested the situation could be attributed to social media. That merely watching YouTube and FaceBook videos of the -- could spark self conscious imitation. Lydia Parker is good friends with two of the girls. Also suffering with the same condition and what are their symptoms like similar problems yeah. Vocal outbursts. Constant movement. One of my good friend she she had seizures. Due to what's going on out she'd like daily just. -- -- spots I have seizures. Many of the parents and students involved feel enough has not been done to investigate environmental causes. And they hang on to the hope that they may soon have answers. For Good Morning America Linda Davis ABC news New York.
This transcript has been automatically generated and may not be 100% accurate.