Report 41: The 2020 SARS-CoV-2 epidemic in England: key epidemiological drivers and impact of interventions
Edward Knock, Lilith K. Whittles, John A. Lees, Paula Guzmán, Robert Verity, Richard G. FitzJohn, Katy A. M. Gaythorpe, Natsuko Imai, Wes Hinsley, Lucy Okell, Alicia Roselló, Nikolas Kantas, Caroline E. Walters, Sangeeta Bhatia, Oliver J. Watson, Charles Whittaker, Lorenzo Cattarino, Adhiratha Boonyasiri, A Djaafara, Keith Fraser, Han Fu, Haowei Wang, Xin Xi, Christl A. Donnelly, Elita Jauneikaite, Daniel J. Laydon, Peter J White, Azra C. Ghani, Neil M. Ferguson, Anne Cori, Marc Baguelin
Abstract
England has been severely affected by COVID-19. We fitted a model of SARS-CoV-2 transmission in care homes and the community to regional 2020 surveillance data. Only national lockdown brought the reproduction number below 1 consistently; introduced one week earlier in the first wave it could have reduced mortality by 23,300 deaths on average. The mean infection fatality ratio was initially ~1.3% across all regions except London and halved following clinical care improvements. The infection fatality ratio was two-fold lower throughout in London, even when adjusting for demographics. The infection fatality ratio in care homes was 2.5-times that in the elderly in the community. Population-level infection-induced immunity in England is still far from herd immunity, with regional mean cumulative attack rates ranging between 4.4% and 15.8%.