Case summary In 2020, UK Health Security Agency (UKHSA) launched a hepatitis C virus (HCV) whole genome sequencing (WGS) clinical service, the first in the UK and to our knowledge the first accredited service of its kind worldwide. The clinical service provides the HCV strain and drug resistance pattern in one test, a game-changing development in HCV diagnostics, replacing the previous, inefficient multi-step process. It was developed by the Antiviral Unit in the Virus Reference Department at UKHSA Colindale to enhance HCV clinical care and public health programs.