“…Estimation of these quantities by public health officials in the United Kingdom (UK) has relied on an ensemble of models which encompass a range of data sources and assumptions ( Park et al., 2023 ). These parameters are traditionally estimated using case data as a proxy for the infection incidence curve ( Cori, Ferguson, Fraser, & Cauchemez, 2013 ; Parag, 2021 ), but methods have also been developed to estimate these parameters from other sources, such as hospitalisations ( Moore, Rosato, & Maskell, 2022 ) and genomic data ( Vöhringer et al., 2021 ). The four nations of the UK (England, Scotland, Wales and Northern Ireland, herein ordered by population size) were recognised globally as having comprehensive SARS-CoV-2 testing surveillance systems ( Clarke, Beaney, & Majeed, 2022 ; Dean, 2022 ; Tapper, 2022 ), comprising of widescale community testing ( Coronavirus (COVID-19) in the UK, 2023 ), nationwide surveys of infection ( Coronavirus (COVID-19) Infection Survey, UK, 2022 ; Real-Time Assessment of Community Transmission (REACT) Study, 2022 ), genomic data ( COVID–19 Genomic Surveillance, 2023 ; The COVID-19 Genomics UK (COG-UK) consortium, 2020 ), and wastewater surveillance ( Morvan et al., 2022 ), but these were largely scaled down from their peak capacity as part of the transition from an “emergency” to “endemic” state in the first half of 2022 ( Coronavirus (COVID-19): Test and Protect - Transition Plan, 2022 ; COVID-19 Response: Living with COVID-19, 2022 ; COVID-19 Test, Trace and Protect Transition Plan, 2022 ; Together for a Safer Future: Wales’ Long-Term Covid-19 Transition from Pandemic to Endemic, 2022 ).…”