England must bring in strict coronavirus controls and accelerate its vaccine programme or risk the burden of more people in hospital and more deaths in the first half of 2021 than the whole of 2020, according to analysis from the London School of Hygiene and Tropical Medicine.
The scientists’ study combined behavioural and epidemiological data with a mathematical model to estimate the future impact of the fast-spreading UK variant of Sars-CoV-2, the virus that causes Covid-19.
They looked at what could happen under different potential control strategies. Even if all of England were placed under tier 4 restrictions from 26 December until 31 January, the “R” value of the new coronavirus variant in England would not be brought below 1.
The R figure reflects the average number of people a person infected with coronavirus passes the disease on to. When the figure is above 1 an outbreak can grow exponentially.
The only scenario that reduced peak ICU burden below the levels of the first wave was to impose the tier 4 system across England after Boxing Day and close schools until the end of January, as well as vaccinating 2 million people per week.
The paper, which is yet to be peer-reviewed or published in an academic journal, has been presented to the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag) and shared with the Scientific Advisory Group for Emergencies (Sage).
The researchers found that the new UK variant – which is prevalent and rapidly outcompeting preexisting variants in at least three regions of England: the south-east, London and the east – was about 56% more transmissible than existing variants.
If current trends continued, they projected the variant could represent 90% of cases by mid-January. Without effective control policies, they added, rapid surges were predicted and there could be more Covid patients admitted to hospital and dying in the first six months of 2021 than in 2020.
The scientists did not find evidence that the new variant leads to more severe disease. However, a higher rate of transmissibility without strict controls could lead bigger waves in the future.
The authors of the analysis had just recently finished calculating the impact of the tiered system and the November lockdown when news of the new variant came to light, noted lead author Dr Nick Davies, who is a member of the Scientific Pandemic Influenza Group on Modelling (SPI-M), which feeds into Sage.
In just five days, the LSHTM researchers incorporated preliminary genomic data and Google mobility data to get an accurate picture of the new variant’s culpability in the rapid rise in cases.
“We were able to rule out the idea that it’s just that these three regions had more social interaction, more opportunities for transmission in the last month and that’s why they’re seeing more cases. So I think we’re able to give pretty strong evidence that that’s not the case, and that it’s probably down to this new variant,” Davies said.
“If our parameter estimates are correct … it seems like [tier 4] alone isn’t enough, so something else might need to be done on top of that. And we’ve looked at school closures because that’s sort of the next obvious thing to do on top of those restrictions,” Davies said, cautioning that the evidence on schools remained unclear.
“We still after all this time don’t really have a very good handle of how transmissible coronavirus is among children, and what role schools play.”
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