WASHINGTON — Health experts across the U.S. and Europe are puzzled as mysterious cases of severe hepatitis continue to rise among young children.
In the U.S., the Centers for Disease Control (CDC) issued an alert Thursday to physicians nationwide to be on the lookout for liver inflammation. The agency has so far confirmed 9 pediatric cases in Alabama in children aged 1 to 6. The CDC said that three of the patients went into acute liver failure, and two ultimately required liver transplants.
The uptick follows a recent outbreak that was first identified in Europe.
Last week, British officials reported 74 cases of hepatitis, or liver inflammation, found in children since January. The usual viruses that cause infectious hepatitis were not seen in the cases, and scientists and doctors are considering other possible sources.
Additional cases of hepatitis had been identified in Denmark, Ireland, the Netherlands and Spain, the European Centre for Disease Prevention and Control said in a statement Tuesday without specifying exactly how many cases were found.
“Mild hepatitis is very common in children following a range of viral infections, but what is being seen at the moment is quite different," said Graham Cooke, a professor of infectious diseases at Imperial College London. Some of the children in the U.K. have required specialist care at liver units and a few have needed a liver transplant.
The liver processes nutrients, filters the blood and fights infections. The infections caused symptoms like jaundice, diarrhea and abdominal pain. Hepatitis can be life-threatening if left untreated.
While it's unclear what's causing the illnesses, a leading suspect is an adenovirus. Only some of the children tested positive for coronavirus, but the World Health Organization said genetic analysis of the virus was needed to determine if there were any connections among the cases.
There are dozens of adenoviruses, many of them associated with cold-like symptoms, fever, sore throat and pink eye. U.S. authorities said the nine Alabama children tested positive for adenovirus and officials there are exploring a link to one particular version — adenovirus 41 — that’s normally associated with gut inflammation.
Public health officials ruled out any links to COVID-19 vaccines, saying none of the affected children were vaccinated.
The WHO noted that although there has been an increase in adenovirus in Britain, the potential role of those viruses in triggering hepatitis is unclear. WHO said there were fewer than five possible cases in Ireland and three confirmed cases in Spain, in children aged 22 months to 13 years.
The U.N. health agency said that given the jump in cases in the past month and heightened surveillance, it was “very likely” more cases will be detected.