Real-time Nowcasting and Forecasting of COVID-19 Dynamics in England: the first wave?

Abstract

England has been heavily affected by the SARS-CoV-2 pandemic, with severe ‘lock-down’ mitigation measures now gradually being lifted. The real-time pandemic monitoring presented here has contributed to the evidence informing this pandemic management. Estimates on the 10th May showed lock-down had reduced transmission by 75%, the reproduction number falling from 2.6 to 0.61. This regionally-varying impact was largest in London of 81% (95% CrI: 77%–84%). Reproduction numbers have since slowly increased, and on 19th June the probability that the epidemic is growing was greater than 5% in two regions, South West and London. An estimated 8% of the population had been infected, with a higher proportion in London (17%). The infection-to-fatality ratio is 1.1% (0.9%–1.4%) overall but 17% (14%–22%) among the over-75s. This ongoing work will be key to quantifying any widespread resurgence should accrued immunity and effective contact tracing be insufficient to preclude a second wave.