The Department of Public Health said Wednesday it has received reports of nine cases under investigation for severe hepatitis in Illinois children under 10 years of age.

That is up from three cases that were reported in April.

Five patients were reported in northern Illinois, two were in the western part of the state, and one each was reported in the central and southern regions. All of the children were hospitalized, and one needed a liver transplant.

No deaths have been reported.

The cases date back to January, with the most recent case occurring this month. Two-thirds of the children tested positive for adenovirus, a common virus that typically causes cold- or flu-like illness.

“IDPH has been working with Illinois healthcare providers to learn of other suspected potential cases in the state and has asked providers to be on the lookout for symptoms and to report any suspected cases of hepatitis in children of unknown origin to local public health authorities,” the agency said in a statement.

The Centers for Disease Control and Prevention said last week that 36 states and territories have reported 180 pediatric patients under investigation over the past seven months.