Development and Evaluation of Molecular Diagnostic Tests for SARS-CoV-2 at English NHS Sites Throughout the COVID-19 Pandemic

The COVID-19 pandemic placed unprecedented pressure on diagnostic services worldwide. The first cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the UK were confirmed on 31 January 2020, prompting National Health Service (NHS) laboratories to scale diagnostic procedures. The demand for testing rapidly exceeded historical norms for respiratory virus diagnostics, necessitating substantial government investment in consumables, assay development, and workforce expansion. This review presents a retrospective evaluation of SARS-CoV-2 diagnostic platforms deployed within the Norfolk and Norwich University Hospital (NNUH) trust and compares them with those implemented by other regional laboratories during the pandemic. It examines the molecular mechanisms, performance, scalability, and specificity of the multiple molecular testing approaches to optimise workflow based on the evolving technology. The integration of complementary platforms through a stratified testing strategy enabled high-throughput population screening while preserving diagnostic resolution for complex respiratory cases, substantially improving laboratory efficiency and resilience. The emerging diagnostic methodologies, RT-LAMP and CRISPR-based assays, are described, and we discuss their potential roles in future outbreaks. We critically evaluate the overall preparedness of UK health services for the COVID-19 pandemic and highlight key priorities for future pandemic preparedness at both local and national levels.