‘Two common viruses’ behind mysterious childhood hepatitis outbreak, say British experts

UK experts believe they have identified the cause of the recent wave of mysterious liver problems affecting young children across the world.

Investigations suggest that two common viruses circulated again after the end of restrictions imposed by governments to control the Covid-19 pandemic – and triggered the rare, but very serious, cases of hepatitis.

More than 1,000 children — many under the age of five — are believed to have been affected in 35 countries.

Some of them, including 12 in the UK, needed a liver transplant to continue living.

In Brazil, suspected cases were investigated by the Ministry of Health, with seven deaths confirmed by mid-June.

Two teams of researchers, from London, England and Glasgow, Scotland, say babies exposed later than usual — because of pandemic restrictions — have lost some early immunity to:

• adenovirus, which typically causes colds and stomach pains
• adeno-associated virus two (AAV2), which normally does not cause disease and requires a co-infecting “helper” virus — such as adenovirus — to replicate

This could explain why some developed unusual and worrisome liver complications.

Three-year-old Noah, who lives in Chelmsford, Essex, needed an urgent liver transplant after becoming seriously ill with hepatitis.

His mother, Rebecca Cameron-McIntosh, says the experience was devastating.

“There was nothing wrong before, and suddenly his health changed. I think that’s what took us by surprise.”

“We just assumed it was a small problem that would be easily resolved — but the picture continued to develop.”

Initially, Rebecca was in line to donate part of her liver — but, after a severe reaction to the drugs used, she ended up in the ICU.

Noah was placed on the transplant list and soon after received a new organ.

His recovery has been good — but he will need to take immunosuppressant drugs for the rest of his life to keep his body from rejecting the new liver.

“There’s something really heartbreaking about that because you follow the rules, you do what you’re supposed to do to protect people who are vulnerable, and then in a horrible, roundabout way, your own child has become more vulnerable because you’ve done what you’re supposed to do. “, says the mother.

Cases like this are rare. Most children who catch these types of viruses recover quickly.

It’s not clear why some develop liver inflammation — but genetics can influence how severe the condition is.

Scientists have ruled out any connection to coronavirus vaccines or Covid-19 itself.

One of the researchers, Professor Judith Breuer, a virology specialist at University College London and Great Ormond Street Hospital, said:

“During the lockdown period, when children weren’t mixing, they weren’t transmitting viruses to each other. They weren’t developing immunity to the common infections that they would normally encounter.”

“When the restrictions ended, the kids started mixing and the viruses started to circulate freely — and suddenly they were exposed with this lack of previous immunity to a whole battery of new infections.”

Experts are hopeful that cases are decreasing, but they are still on the alert for new cases.

Professor Emma Thomson, who led the research at the University of Glasgow, said there were still many unanswered questions. “Larger studies are urgently needed to investigate the role of AAV2 in pediatric hepatitis.

“We also need to understand more about the seasonal circulation of AAV2, a virus that is not routinely monitored — it could be that a spike in adenovirus infection coincided with a spike in AAV2 exposure, leading to an unusual manifestation of hepatitis in susceptible children.