Encouraging twice weekly COVID testing at home is unlikely to reduce transmission and is a “misguided policy”, public health experts warn today.
Writing in The BMJ, public health consultants Angela Raffle, of the University of Bristol Population Health Sciences and UK National Screening Programmes, and Mike Gill, from London,UK, say coronavirus tests per case detected are already higher in the UK than anywhere in the world, while the value of adding low-risk testing is unknown.
These tests are being introduced without plans to measure the costs and consequences and despite the UK failing to test and support in isolation everyone with symptoms and their contacts, they say.
The challenge for the UK is to use the information learned over the past year, take advantage of the new laboratory capacity and the availability of rapid tests to best effect.
“Current efforts are undermined by secrecy, quality failures, underused capacity, and a misplaced focus on low yield uses,” they write.
“Both the laboratories and the rapid tests could be targeted to deliver a substantially more effective and cost effective testing service founded on the public service principles of sound evaluation, strong ethics, high quality, and full transparency.”
The publication also features a debate about the effectiveness of wearing masks outdoors to help reduce COVID-19 transmission.
Babak Javid at the University of California San Francisco, USA, and colleagues argue that individuals should wear masks outdoors, particularly at large outdoor gatherings with prolonged close interactions.
They write that mass protests in support of the Black Lives Matter movement did not result in an increase in cases, unlike the mass outdoor Sturgis Motorcycle Rally in South Dakota, USA, which is believed to have been a huge superspreading event.
They believe this is because the Sturgis Rally was associated with lower compliance with measures such as mask wearing and physical distancing. They also point to data from the USA and Germany that demonstrates regions with public mask mandates have had a lower impact from the virus, while countries with early adoption of face coverings for the public also achieved an earlier acceptance of a social norm during the pandemic.
“Wearing masks outdoors, particularly at large outdoor gatherings such as sporting events or other settings where it will be difficult to maintain physical distance for prolonged periods, which may have a low but measurable risk of seeding a superspreading event – as well as normalising mask wearing behaviour in general – will bring benefits in reducing risks during the pandemic phase of COVID-19,” they add.
However, Dr Muge Cevik at the University of St Andrews and colleagues argue that efforts should focus on reducing indoor transmission because there no confirmed sizeable COVID-19 “superspreader” events have been outdoors-only.
They say the Sturgis Rally and the Rose Garden outbreak at the White House had sustained indoor components over a number of days, with an epidemiological investigation of Sturgis Rally finding cases linked to restaurants and workplaces.
They write that outdoor mask mandates may be popular in some settings. “However, these mandates do little to tackle the real transmission risks or to address outcomes of socioeconomic inequities and structural racism, driving a disproportionate number of the infections and consistent disparities observed worldwide,” they conclude.
Raffle AE, Gill M. Mass screening for asymptomatic SARS-CoV-2 infection. BMJ 29 April 2021 [abstract]
Javid B, Bassler D, Bryant MB et al. Should masks be worn outdoors? BMJ 29 April 2021 [abstract]
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