Baseline data & proportion of pre-symptomatic and asymptomatic
cases.
Based on the ONS survey data, we modelled the impact of face coverings
based on 2,800 community cases per day. Of these, 80% are estimated to
be due to transmission from pre-symptomatic and asymptomatic cases.
These generate a baseline figure for assessment of the impact of face
coverings of 2,240 community cases.