CHICAGO (WLS) -- Illinois has nine potential cases of severe hepatitis in children under 10, health officials said.
That number is up from just three cases reported last month.
The cases date back to January, and the most recent had the onset of symptoms in May, IDPH said.
Two-thirds of the children tested positive for adenovirus, which is a common virus that typically causes cold or flu-like illness, health officials said. 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 parts of the state.
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State health officials said all of them were hospitalized and one needed a liver transplant, but no deaths were reported.
The CDC is investigating 180 potential cases of severe hepatitis throughout the country.
Health officials continue to remind parents and healthcare providers to be on the lookout for symptoms and to report any potential cases to the health department.
The CDC said that symptoms of hepatitis, or inflammation of the liver, include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, light-colored stools, joint pain, and jaundice and can be caused by viruses.
These cases appear to have an association with adenovirus 41. Adenoviruses spread from person-to-person and most commonly cause respiratory illness, but depending on the type, can also cause other illnesses such as gastroenteritis (inflammation of the stomach or intestines), conjunctivitis (pink eye), and cystitis (bladder infection), IDPH said. Adenovirus type 41 also typically presents as diarrhea, vomiting and fever, and is often accompanied by respiratory symptoms. While there have been case reports of hepatitis in immunocompromised children with adenovirus infection, adenovirus type 41 is not known to be a cause of hepatitis in otherwise healthy children, officials added.
The CDC continues to recommend children be up to date on all their vaccinations, and that parents and caregivers of young children take the same everyday preventive actions that it recommends for everyone, including washing hands often, avoiding people who are sick, covering coughs and sneezes, and avoiding touching the eyes, nose or mouth.