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expert reaction to SPI-M document mentioning that in England we are breaching the number of infections and hospital admissions in the Reasonable Worst Case planning scenario that is based on COVID-S’s winter planning strategy

The Scientific Pandemic Influenza Group on Modelling, Operational sub-group (SPI-M-O) have released a consensus statement on COVID-19, mentioning that, in England, we are breaching the number of infections and hospital admissions in the Reasonable Worst Case planning scenario that is based on COVID-S’s winter planning strategy.


Dr Amitava Banerjee, Associate Professor in Clinical Data Science and Honorary Consultant Cardiologist, Institute of Health Informatics, UCL, said:

“The SPI-M-O statement acknowledged that infection rates and hospital admissions were almost certain to exceed the worst case winter planning scenario.  It recommended that if infection rates were to fall, ‘this exceedance of the reasonable worst case scenario might only continue for three to four weeks.’  In addition, the report found that for delays in testing and tracing beyond 24 hours made contact tracing ineffective.

“There is now unequivocal evidence from multiple sources over weeks, if not months, that infection rates have been rising, and that current suppression measures are simply not working.  Moreover, the report underscores the need for reliable and effective testing and tracing to maintain control of COVID-19, which is lacking at present.  The infection rate has to be kept as low as possible to avoid direct effects through infection, indirect effects through strain on the NHS, and further economic uncertainty.  The data seem to point in the direction of a national lockdown as the best way to bring the infection rate down.”


Prof Sheila Bird, Formerly Programme Leader, MRC Biostatistics Unit, University of Cambridge, said:

“REACT-1 has released an urgent interim report on the 6th round of its swab-testing (75% sensitivity assumed).  In total, 86,000 persons aged 5+ years participated during 16th to 25th October 2020, when England might have had (but did not) a two to 3-week circuit-breaker to coincide with school holidays.  See Table for REACT-1’s estimate for the number of new SARS-CoV-2 infections daily in England.

“See Table also for the estimates that ONS Infection Survey released today for the number of new SARS-Cov-2 infections daily in England during the week of 10th to 16th October; and 17 to 23rd October.

“Finally, see Table for SPI-M-O’s consensus estimates, derived from modelling studies, for the number of new infections in England daily.  These estimates were prepared on 7th and 14th October for next-day meetings of UK’s Scientific Advisory Group in Emergencies (SAGE) for SARS-CoV-2.  But, they were not released to the public until today: 2 to 3 weeks later.  Yet the doubling time for pandemic infections in England is less than 2 weeks, as Table indicates.

“REACT-1 estimates would be expected to be higher than by ONS Infection Survey due to their different sampling frames (NHS register versus address file); and estimates from modelling studies, which are informed – inter alia – by COVID-mention hospitalisations and deaths, do not fully reflect behavioural changes in infection-risk in the most recent two weeks and so the SPI-M-O consensus is intermediate between the pair of empirical studies.

“Delays in sharing the valuable scientific insights offered to UK Government by its SPI-M-O group should not be allowed to exceed the doubling time of the pandemic!

“For the second wave, may we please add timeliness to welcome transparency when it comes to SAGE documents, so that when Ministers speak we can know what their astute scientific advisers advise, SPI-M-O especially.  For example, already in their 14 October Consensus, SPI-M-O had warned that England was breaching the number of infections and hospital admissions in the Reasonable Worst Case winter planning scenario and that the number of deaths was also highly likely to exceed reasonable Worst Case levels by the end of October.”


Dr Christopher Jewell, Senior Lecturer in Epidemiology, Lancaster University, said:

“Of course breaching the reasonable worst case scenario is worrying, but we must remember that the previous RWC was based on data we had in February and March when we know we were only detecting a small fraction of true cases.  We now have a much more capable testing programme in place, meaning we are picking up a much higher proportion of the true number of cases compared to back in March – this almost certainly accounts for the apparently huge spike in cases compared to the previous peak in April/May.”


Prof Azra Ghani, Chair in Infectious Disease Epidemiology, Imperial College London, said:

“Reasonable worst case scenarios are used by government for planning purposes; however it is worth bearing in mind that any such scenario requires assumptions to be made about future transmission levels that are difficult to predict.  It is therefore more important to focus on the current stage of the epidemic and recent trends in infections.  Whilst there has been some indication of a slowing in the rate of growth of the epidemic in parts of the country, R remains above 1 in all areas and therefore infections, hospital admissions and deaths can be expected to continue to rise in the near-term.  It is therefore critical that we reduce transmission further through reducing social contacts and adhering to public health guidance in order to reverse the epidemic and ensure that the NHS is not overwhelmed as we enter the busy winter period.”



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