Common viruses may be reason for hepatitis cases in children, researchers find

The research, published in the journal Nature homes, found that adeno-associated virus 2, or AAV2, a virus not previously known to cause illness - was found in 93% of cases.

Another virus also found was was adenovirus type 41, which has been previously identified as a potential suspect in the illnesses by the Centers for Disease Control and Prevention (CDC) and brings with it symptoms such as diarrhoea, vomiting and nausea.

Researchers also found a herpes virus, an enterovirus and Epstein-Barr virus - this can cause mononucleosis (also known as the kissing disease).

The findings do not prove that co-infections directly cause severe hepatitis, but they provide important clues towards that.

The study focused on 16 children in the US with severe hepatitis.

Researchers compared the results to 113 pediatric patients who were either healthy or had liver problems.

Last year, two other studies also detected the Adeno-associated virus (AVV2) in severe pediatric hepatitis cases in the United Kingdom.

"Similar findings by three independent studies give strong credibility to the results," Thomas Baumert, head of the Inserm Research Institute for Viral and Liver Diseases and the University of Strasbourg in France said in a statement.

In 2022, the World Health Organisation (WHO) reported 1,010 probable cases of severe acute hepatitis in 35 countries around the world.

What is Hepatitis and what are the symptoms?

Hepatitis is a condition that affects the liver and can be caused by infection with a virus, according to the NHS.

Some of the symptoms include:

• Stomach pain
• A high temperature
• Loss of appetite
• Dark urine
• Fatigue
• Muscle and joint pain
• Nausea

Between 2021-2022, WHO reported 435 probable cases of severe acute hepatitis in the US, with 24 cases requiring liver transplants.

According to the CDC, in 2021, five children had been identified with hepatitis in Alabama.

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"The children had significant liver illness, including some with liver failure, with no known cause," the CDC said.

"The five children tested negative for hepatitis A, hepatitis B, and hepatitis C viruses and tested positive for adenovirus, a common virus that typically causes cold or flu-like illness, or more rarely stomach or intestine problems," they added.

In the UK, as of 2022, there were 250 confirmed cases of acute non-A-E hepatitis identified in children under the age of 16.

The GOV.UK website said between 21 January and 13 June 2022, "12 children in the UK meeting the case definition have required liver transplantation; no cases resident in the UK have died."