AAV2 and Paediatric Hepatitis

In March 2022, young children across Scotland arrived at hospital with symptoms of paediatric hepatitis. The cause of their hepatitis was unclear. Without knowing the cause, it was difficult to know how to treat the children and how to prevent the outbreak from progressing.

To find the missing piece of the puzzle, a research investigation was activated which led to the discovery that a virus, called AAV2, was likely causing the hepatitis in these children. Many institutions such as the CVR, NHS, and Public Health Scotland were involved in this journey.

From Illness to Insight: Exploring a Journey through Paediatric Research

From Illness to Insight: Exploring a Journey through Paediatric Research

In February 2024, we hosted an event which celebrated the collaborative research and family involvement in this outbreak response.

This video gives families an insight into what they could expect from participating in research.

Find out more 

Read our Recommendations Report

Part of the event involved bringing together key stakeholders of the outbreak response, including clinicians, clinical research teams, CVR research leads, and representatives from Public Health Scotland Scottish, The National Blood Transfusion Service and ISARIC4C joint chief investigator. They discussed successes and areas of improvements and put together this report.

AAV2 Recommendations Report

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Research Outputs

In March 2023, the research article titled 'Adeno-associated virus 2 infection in children with non-A–E hepatitis' was published in Nature. The peer-reviewed study, which was led by researchers at the University of Glasgow in collaboration with the Royal Hospital for Children in Glasgow, Public Health Scotland (PHS) and ISARIC (International Severe Acute Respiratory and emerging Infections Consortium) WHO Clinical Characterisation Protocol UK (CCP-UK), found that the common virus AAV2 (adeno-associated virus 2) was present in a range of different samples taken from children with acute unexplained hepatitis. In contrast, AAV2 was not found to be commonly present in samples taken from children in the control groups. Researchers believe that AAV2 virus may have played a key role in the development of acute hepatitis in a small number of young children around the world.

As part of the CVR's digital media platform, Research Goes Viral, host Stephen Devlin takes a deep dive into the publication with lead author Dr Antonia Ho, Bioinformatician Dr Richard Orton and Pathologist Dr Vanessa Herder. The podcast explores the importance of collaboration for a rapid response such as this to be possible. 

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Read Nature the article 

Watch the podcast

Policy Contribution

CVR identified AAV2 as the likely pathogen involved in an outbreak of unexplained hepatitis. Clinical recruitment and co-ordination and characterisation was led by Prof Toni Ho. Research response was led by Prof Emma Thomson, involving Dr Richard Orton, Prof David Robertson, Dr Ana Filipe, Dr Vanessa Herder and Dr Patawee Asamaphan. This was detected in real time, during the outbreak, and was later verified by Gt Ormond St and CDC/Charles Chiu in the USA (6 months later). 

Investigation into acute hepatitis of unknown aetiology in children in England: