(WTVO) — Illinois health officials said on Wednesday night that they have received reports of nine children with potential cases of severe hepatitis.

That is up from just three cases last month. All of the children were under 10-years-old and hospitalized. One patient needed a liver transplant.

The Centers for Disease Control and Prevention is encouraging parents and caregivers to be aware of the symptoms of hepatitis, specifically the yellowing of the skin or eyes. Additional symptoms include fever, fatigue, nausea and vomiting.