JOHNSON CITY, Tenn. (WJHL) — An E. coli outbreak during a school trip to the Appalachian Fairgrounds is continuing to leave children in the hospital.

According to the Northeast Regional Health Office, eight children have been hospitalized and four others seriously ill. The kids who have contracted the bacteria were students in Washington County, Tennessee and Sullivan County.

15-month-old River Hefflin remains hospitalized at East Tennessee Children’s Hospital in Knoxville after he contracted E. coli. His brother was one of the students who was on a field trip to the Appalachian Fairgrounds.

His mother, Deidre, said that River’s dialysis to keep his kidneys working is showing positive signs. However, she did say that an MRI confirmed that River had suffered brain damage. He’ll likely have to learn how to walk and talk again, she said.

“We were in serious need of a miracle,” Hefflin said. “When he got out of surgery and they brought him back up for the dialysis to start the peritoneal dialysis that runs through his abdomen, he started having more neurological issues.”

According to a statement from Northeast Regional Health Office Medical Director Dr. David, Kirschke, the illnesses occurred after elementary school classes visited an animal exhibit at the fairgrounds.

Appalachian Fairgrounds Manager Phil Booher said during a phone call that he wasn’t sure what animals the guest came into contact with.

Deidre Hefflin said that there have many tense and scary moments since River has been in the hospital. River remains in the hospital, but he’s on the road to recovery. Hefflin said that he’s making small strides forward.

“You can tell that he’s starting to become responsive to our voices,” Hefflin said. “He’s recognizing our voice and opening his eyes so that’s good to see.”