Modelling the impact of the mandatory use of face coverings on public
transport and in retail outlets in the UK on COVID-19-related
infections, hospital admissions and mortality
Abstract
Introduction The rapid spread of the pandemic caused by the severe acute
respiratory syndrome coronavirus 2(SARS-CoV-2)(COVID-19) virus resulted
in governments around the world instigating a range of measures,
including mandating the wearing of face coverings on public transport/in
retail outlets. Methods We developed a sequential assessment of risk
reduction provided by face coverings using a step-by-step approach. The
United Kingdom Office of National Statistics(ONS) Population Survey data
was utilised to determine the baseline total number of community-derived
infections. These were linked to reported hospital admissions/hospital
deaths to create case admission risk ratio/admission-related fatality
rate. Results Overall, we show that only 7.3% of all community-based
infection risk associates with public transport/retail outlets. The
reported weekly community infection rate was 29,400 new cases at the
start (24th July). The rate of growth in hospital admissions and deaths
for England was around -15%/week, suggesting the infection rate, R, in
the most vulnerable populations was just above 0.8. In this situation,
average infections over the evaluated 13week follow-up period was
9,517/week. With face covering of 40% effectiveness, this reduced
average infections by 844/week, hospital admissions by 8/week and deaths
by 0.6/week; a fall of 9% over the period total. If, however, the
R-value rises to 1.0, then average community infections would stay at
29,400/week and face coverings could reduce average weekly infections by
3,930, hospital admissions by 36 and deaths by 2.9/week; a 13%
reduction. These reductions should be seen in the context of
102,000/week all-cause hospital emergency admissions in England and
8,900 reported deaths in the week ending 7thAugust 2020. Conclusion We
have illustrated that the policy on mandation of face coverings in
retail outlets/on public transport may have limited value in reducing
hospital admissions/deaths. Impact appears small compared to all other
sources of risk, thereby raising questions regarding effectiveness of
the policy.