Child hepatitis outbreak could stem from isolation rules

THE mysterious hepatitis outbreak in children is linked to cases of the common cold that surged after a loss of immunity owing to two years of lockdown isolation, scientists believe.

Clinicians have finally found what they think is the cause of the spate of more than 260 cases of the liver condition, which led to 12 children needing a transplant.

Various theories were suggested, including that is was a side-effect of Covid infection or the vaccine. However, evidence reveals that an innocuous virus called AAV2 (adeno-associated virus 2) and adenoviruses, a common cold pathogen, are probably to blame.

Adenoviruses thrive every winter, but this spring saw a spike in infections because after two yearsof lockdown and social distancing the level of immunity to the virus was low.

Because of that the number of people vulnerable to the virus was larger than normal, leading to a spike once social mixing returned to normal.

AAV2 can infect cells but it cannot replicate and do damage so it needs to ride piggyback on another virus to do so. It has never been shown to harm humans before but academics found signs that AAV2 and adenoviruses may work in tandem to cause hepatitis.

“Now that there are children back at school, mixing ... lots of seasonal viruses are transmitting and circulating outside what we would normally expect them to, and this large wave [of adenovirus infections] is not typical for this time of year,” said Dr Antonia Ho, of the Mrc-university of Glasgow centre for virus research. He also co-wrote one of the two studies on the outbreak that were published yesterday.

A separate study, run in part by the UK Health Security Agency, found 94 per cent of the unexplained hepatitis patients had AAV2 in their systems. In the general population, the virus is found in just six per cent of people.