A children's hospital in Wisconsin says eight teenagers who vape were hospitalized this month with severe lung damage, reports the Milwaukee Journal Sentinel.

Many of the teens responded to steroid treatment and were released while one remains hospitalized. Each of the teens admitted to using a vape weeks and months before they were treated.

"The eight patients have had a variety of illnesses, some of which have been hospitalized in our Intensive Care Unit and required significant therapy to help them breathe," said Dr. Michael Gutzeit, chief medical officer.

Gutzeit said the Wisconsin Department of Health Services was investigating the root cause.

"They are investigating the cause, and perhaps, the origin of that – whether it may be a singular batch, or whether there may be other factors involved," Dr. Gutzeit said.

Jonathan Meiman, the chief medical officer with DHWSI said teens had mentioned they vaped nicotine and THC.

"We have a common theme of vaping," Jonathan Meiman said. "We do not know of one product."

Doctors at Children's Hospital in a statement encouraged parents to sit down with their children and discuss the health risks of vaping.