Two new UK research papers explain the likely causes of sudden onset hepatitis seen in children aged 10 and under, is due to co-infection with adenovirus 41F and a second virus AAV2 (or less commonly HHV6).

An investigation led in Scotland (external website) by the University of Glasgow, the Medical Research Council, Centre for Virology Research, and supported by Public Health Scotland (PHS), and a second investigation led by Great Ormond Street Hospital (external website) were published today, 25 July 2022. The extensive investigations explored various factors which could have acted as a trigger for the illness, including an infectious cause, exposure to environmental toxins, and genetic factors.

Cases were initially reported in April 2022 and as of 25 July 2022, the total number of cases identified in Scotland was 38. No new cases were identified in Scotland between 13 June 2022 and 25 July 2022.

The Scottish research identified an additional genetic factor which may explain why some children developed severe illness whilst others did not. The investigation noted the presence of a marker showing a genetic predisposition in cases of severe disease but found this marker much less commonly in the general population.

Explaining why only some children go on to develop hepatitis, Dr Jim McMenamin, Head of Health Protection, Consultant Epidemiologist at PHS, said:

“These findings are important. They appear to explain why not all young children with adenovirus infection develop severe disease. Importantly, children need to have a co-infection with an additional second virus that can affect the liver and also have a specific genetic make-up before they go on to develop severe disease.

“Whilst its reassuring that cases have now fallen, we continue to remind parents and care-givers that they should continue to ensure children practice good hand and respiratory hygiene to help reduce the spread of common infections, like adenoviruses.

“If a child shows signs of jaundice, where there is a yellow tinge in the whites of the eyes or on the skin, then parents should contact their GP or other Health Care professional”.

Last updated: 06 October 2022