A chain of events potentially triggered by undetected infection with the SARS-CoV-2 coronavirus could be causing the mysterious cases of severe hepatitis being reported in hundreds of young children around the world, researchers suspect.

Children with COVID-19 have a significantly increased risk of liver dysfunction afterwards, according to a report published on medRxiv on Saturday ahead of the peer review.

But most children with acute hepatitis – which is generally rare in this age group – do not report previous SARS-CoV-2 infection. Instead, the majority were found to be infected with an adenovirus called 41F, which is not known to attack the liver.

It’s possible the affected children, many of whom are too young to be vaccinated, may have had mild or asymptomatic COVID infections that went unnoticed, a separate research team in The Lancet Gastroenterology & Hepatology suggests.

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The WHO says at least 228 probable cases of hepatitis in children have been reported, with more being investigated

If that were true, the theory goes, lingering particles of coronavirus in the gastrointestinal tract in these children could prime the immune system to overreact to adenovirus-41F with high levels of inflammatory proteins that ultimately damage the liver.

“We propose that children with acute hepatitis be screened for the persistence of SARS-CoV-2 in the stool” and for other signs that the liver damage is occurring, since the coronavirus spike protein is a “superantigen” that detects the virus Immune system oversensitive. Said.