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Details of England’s regional tiers has been published today, as described by Matt Hancock in the Commons.
Comment on the Liverpool mass testing, as mentioned in the Downing Street press conference:
Prof Sheila Bird, Formerly Programme Leader, MRC Biostatistics Unit, University of Cambridge, said:
“A published protocol, for all to read, which detailed the UK government’s and Liverpool’s prior expectations from Liverpool’s mass asymptomatic serial testing (MAST) is lacking.
“Today’s No10 briefing might have presented some key results from Liverpool’s mass asymptomatic serial testing which uses the INNOVA test1. The Prime Minister cited the “number of lateral flow tests performed” – without differentiating frequent-testers from 1st attenders.
“Please may we all know:
a) the number of lateral flow tests (LFTs) that asymptomatic citizens in Liverpool accessed within 2-weeks (defined as 6-20th November; or 9-23rd November if we discount the initial set-up days); NAL
b) the number of asymptomatic citizens in Liverpool who undertook 1 or more LFTs in the 2-week period specified above (why – because twice-weekly testing was an aspiration; my prior expectation was 20% to 40%); NAL1
c) the number of asymptomatic citizens in Liverpool who were LFT-positive at their 1st LFT (my prior expectation was “true” asymptomatic prevalence rate of between 1 in 300 and 1 in 75, 1 in 200 being most likely); NAL1+ve
d) the proportion of asymptomatic citizens who were LFT-positive at their 1st LFT whose confirmatory RT-PCR test was negative (my prior expectation was 30% to 65%);
e) the number of asymptomatic citizens in Liverpool who undertook their 1st LFT at a location where RT-PCR corroboration was offered and accepted, irrespective of LFT-result; NAL1+RT
f) Cross-tabulation of LFT versus RT-PCR result for some 20,000 citizen-participants at e).
“I’d need clear answers to the above basic questions before I’d give credence to claims about the success of Liverpool’s mass asymptomatic serial testing.”
1 https://www.bmj.com/content/371/bmj.m4469
Dr Flavio Toxvaerd, University Lecturer at the Faculty of Economics, University of Cambridge, who specialises in the economics of infectious diseases and economic epidemiology, said:
“The government’s announcement of a return to a tiered system is to be welcomed. A rational containment strategy should whenever possible be sensitive to local conditions in order to minimise the social and economic damage caused by the restrictions. At the same time, measures in each area must be coordinated with those in neighbouring areas, as commuters and shoppers may helps the disease spread from one to the other. Today’s announcement suggests that these issues have been actively considered.
“The updated tier system is more restrictive than the one that was in place before the lockdown and this could have the desired effect of more effectively keeping infection under control.
“Now that vaccines are on the horizon, it is even more important to redouble our efforts to contain the disease, so more people can make it safely through the winter and benefit from the protection that they provide.”
Prof Lawrence Young, Professor of Molecular Oncology, Warwick Medical School, said:
“While recognising the crucial need for continued restrictions, the new 3 tier approach remains very confusing. We can see some evidence that the current lockdown in England has had an effect – the number of cases appear to be reducing but this could easily flare up again. A particular concern is the opening of shops across all tiers and what this will means for people desperate to shop for Christmas. If we’ve learnt anything about this virus it’s that it is very infectious and we mustn’t squander what we have done so far to stop the virus spreading. The 5 day Christmas bubble is very worrying. The virus doesn’t know that it’s Christmas and it is inevitable that these relaxed restrictions will result in a surge in infections. None of us would want to give our elderly relatives COVID for Christmas!”
Prof Jonathan Ball, Professor of Molecular Virology, University of Nottingham, said:
“There has been much focus on what the Christmas festivities will be like, but the announcement that much of England will be experiencing severe restrictions up to then is a stark reminder that the virus is very much out there and still circulating freely. It will be important for everyone to take the threat seriously and to minimise the risk to themselves and others by reducing social interactions – especially indoors – as much as possible. The announcement of the real possibility of effective vaccines being ready soon provides light at the end of the tunnel, so we need to do all that we can between now and then to minimise the harm that the virus can do to vulnerable people in our society and to our NHS. We might have come out of lockdown but that doesn’t mean the party season should commence.”
https://www.gov.uk/guidance/full-list-of-local-restriction-tiers-by-area
All our previous output on this subject can be seen at this weblink:
www.sciencemediacentre.org/tag/covid-19
Declared interests
Prof Sheila Bird: “SMB serves on the Royal Statistical Society’s COVID-19 Taskforce, has a long-standing interest in statistical reporting standards and chaired the RSS Working Party on Performance Monitoring in the Public Services.”
None others received.