Link to report here:
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1073704/acute-hepatitis-technical-briefing-2.pdf
There have been at least 163 cases in the UK since the beginning of 2022. 11 cases required a liver transplant. None of the UK cases have died.
Of the 163 cases, 126 were tested for adenovirus infection with 91 cases positive for adenovirus (72% of tested cases). Though 20 of the negative cases were not tested on whole blood samples, so may not be definitively negative. Where sequencing was possible, all were for adenovirus type 41F.
132 cases were tested for coronavirus infection. Only 24 cases were positive for SARS-COV-2 (18% of tested cases). Serological testing is ongoing, but given the high population seroprevalence of coronavirus antibodies it may not be informative.
Coronavirus vaccination has been ruled out as a cause as fewer than 5 of the older children are vaccinated
In the UK's syndromic surveillance, there are slight increases in emergency department admissions for liver disease for 1 to 4 year olds and 5 to 14 year olds compared to previous years, but the increases aren't large.
There have been increases in adenovirus infections among young children in 2022 compared to previous years. This has been seen with other respiratory pathogens as well. Likely related to increased social mixing as pandemic restrictions eased and reduced population immunity from the pandemic mitigation.