Mystery Hepatitis in Children Still Spreading Across the World, No Cause Identified

Health care workers are seen in a recent file photo. Ariana Drehsler/AFP via Getty Images

The worldwide outbreak of mysterious hepatitis cases among children first reported in Georgia in April is still ongoing. Investigators have confirmed hundreds of cases globally, while officials in more U.S. states have recently confirmed cases.

Federal authorities in the United States say they are investigating 274 possible child hepatitis cases, according to data from the Centers for Disease Control and Prevention (CDC), which has reported cases in 39 states of unknown origin. Officials in the United States and other countries have said it’s not clear what’s going on with the hepatitis outbreak.

During a news conference on Wednesday, World Health Organization Director Tedros Adhanom Ghebreyesus confirmed more than 700 possible cases of child hepatitis. At least 38 have required liver transplants, WHO said, which added that 10 have died. There are another 99 cases that need to be classified, the agency said.

And on Thursday, the Kentucky Department of Public Health confirmed six cases of child hepatitis of unknown origin in the state.

With this outbreak, hepatitis cases have been more severe and a “higher proportion” of child patients have developed “acute liver failure compared with previous reports of acute hepatitis of unknown aetiology in children,” WHO said.

“While adenovirus is a plausible hypothesis as part of the pathogenesis mechanism,” said the U.N. health agency, “further investigations are ongoing for the causative agent; adenovirus infection (which generally causes mild self-limiting gastrointestinal or respiratory infections in young children) does not fully explain the more severe clinical picture observed with these cases.”

During early CDC reporting about a group of hepatitis cases in Alabama, the agency said that all nine children with the disorder tested positive for adenovirus, which is a common virus that can cause cold-like symptoms. In several news conferences, CDC officials have said it’s still not clear that adenovirus can cause the condition.

Health officials with the CDC and WHO have previously said they do not believe COVID-19 vaccines appear to be linked to the hepatitis cases as many of the children who have developed the condition haven’t received the vaccine. They have also ruled out COVID-19 itself as a cause.

Hepatitis is a term that refers to inflammation of the liver and is generally caused by a viral infection. The viruses hepatitis A, B, and C are commonly associated with the condition, although officials say that liver inflammation can also be caused by long-term or heavy alcohol usage, drug overdoses, prescription drugs, over-the-counter drugs like acetaminophen, and toxins.

Symptoms of hepatitis include jaundice, or the yellowing of the skin or whites of the eyes, as well as nausea, vomiting, diarrhea, dark-colored urine, joint pain, a loss of appetite, fever, and fatigue, according to the Mayo Clinic and other health officials.