DURHAM, N.C. (WNCN) – The Centers for Disease Control and Prevention is asking physicians nationwide to be on the lookout for unusual cases of severe hepatitis and adenovirus infection in children.

The agency issued an advisory on Thursday.

Hepatitis refers to inflammation of the liver, a condition that can result in diarrhea, abdominal pain, nausea, and vomiting.

Two cases were identified in North Carolina involving school-aged children last month.

The state health department tells CBS17 the two children didn’t need a liver transplant and have since recovered.

Health officials say no cause has been found and no common exposures were identified.

“Adenovirus usually causes common cold symptoms like runny nose or a cough, sometimes upset stomach or diarrhea but in the small number of children in the united states and worldwide, it seems to also be causing this year acute viral hepatitis,” said Dr. Kitty O’Hare, pediatrician with Duke Health.

Nine other cases have been identified in Alabama in children aged 1 to 6 over a four-month period.

Two of the children needed a liver transplant.

In each case, the child tested positive for adenovirus.

O’Hare encourages parents to keep an eye out for symptoms.

“If you notice that your child is not urinating very much, if they’re refusing to eat, if they have a fever for more than a couple of days, it’s always a good idea to reach out to your healthcare provider to get some guidance,” O’Hare said.

NCDHHS is keeping a lookout for potential cases in coordination with poison control and healthcare systems across the state.