Judith Breuer is Professor of Virology at UCL and Clinical lead for Virology at Great Ormond Street Hospital for Children. Professor Breuer led the metagenomic discovery of AAV2 as the cause of the  paediatric hepatitis outbreak affecting >1000 children worldwide in 2022. This has led to further work on the pathogenesis of hepatitis associated with rAAV gene therapy. She chairs and is a member of several national government and UKHSA committees on vaccines and infection.