Experts still not sure mutant strain is more deadly despite Boris’ dire warnings
Scientists say they were ‘surprised’ to hear Boris Johnson’s grave warnings about the new strain of coronavirus because they are still ‘only around 50%’ sure it is more deadly. The Prime Minister announced to the public yesterday that the latest studies indicate the variant first found in Kent is associated with a higher death rate.
Boris Johnson announced yesterday the mutant strain of the virus is causing more deaths (Pictures: Getty/Rex)
Scientists say they were ‘surprised’ to hear Boris Johnson’s grave warnings about the new strain of coronavirus because they are still ‘only around 50%’ sure it is more deadly. The Prime Minister announced to the public yesterday that the latest studies indicate the variant first found in Kent is associated with a higher death rate.
But some experts say the findings are still not conclusive and more data is needed before the increased risk of mortality is fully understood. Boris Johnson – flanked by Chris Whitty and Sir Patrick Vallance – choose to announce the news from Downing Street, hours after first being informed of the latest developments himself.
Mr Johnson said: ‘Since the beginning of this pandemic, we’ve tried to update you as soon as possible about changes in the scientific data or the analysis. ‘So I must tell you this afternoon that we’ve been informed today that, in addition to spreading more quickly, it also now appears that there is some evidence that the new variant – that was first identified in London and the south east – may be associated with a higher degree of mortality.’ Dr Mike Tildesley, a member of the Sage subgroup the Scientific Pandemic Influenza Group on Modelling (Spi-M), said that it was still too early to be drawing ‘strong conclusions’. He said: ‘I was actually quite surprised the news had been announced at a news conference. ‘It seems to have gone up a little bit from about 10 people per thousand to about 13 which is quite a small rise but it’s based on a relatively small amount of data.
Boris Johnson during yesterday’s press conference (Picture: Getty)
‘I would be wanting to wait for a week or two more, monitoring a little bit more before we draw really strong conclusions about this.’ Speaking on BBC Breakfast he added: ‘I just worry that where we report things pre-emptively where the data are not really particularly strong.’ Sir Patrick, the country’s chief scientific officer, repeatedly stressed that the evidence around the increased severity of the Kent strain was ‘weak’ and there’s a lot of ‘uncertainty’ about the numbers. ‘These data are currently uncertain and we don’t have a very good estimate of the precise nature or indeed whether it is an overall increase, but it looks like it is,’ he said. The warnings about the new variant came from the Government’s New and Emerging Respiratory Virus Threats Advisory Group, a sub-committee of Sage.
Ambulance crew wheel a stretcher outside the emergency department at the the Royal London Hospital yesterday (Picture: Getty)
It was based on three studies conducted by the London School of Hygiene and Tropical Medicine, Imperial College London and the University of Exeter. These estimated that the increased risk of death was between 1.35 times higher and 1.91 times higher. All three studies took a small sample of the deaths that have occurred since the variant emerged late last year and applied different methodologies to assess the risk of mortality. Nervtag concluded there was a ‘realistic possibility’ the new strain is more deadly but this phraseology is used by scientists when they are around 50% sure of something.
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Public Health England medical director Dr Yvonne Doyle said the findings are still not ‘absolutely clear’ and more studies are needed. ‘There are several investigations going on at the moment. It is not absolutely clear that that will be the case (the new strain is more deadly). It is too early to say,’ she told the BBC Radio 4 Today programme. ‘There is some evidence, but it is very early evidence. It is small numbers of cases and it is far too early to say this will actually happen.’ The new variant was not found to have driven up death rates among patients already in hospital but may increase the risk of going into hospital in the first place. It’s thought the true picture will become clearer over the next few weeks as more data becomes available.
Professor Peter Horby, who chairs Nervtag, defended the decision to go public with the findings but urged people to ‘keep things in perspective.’ He told BBC Breakfast: ‘There are some limitations in the data so we need to be cautious with the interpretations but it is important that people understand that we are looking at this and this may be true. ‘If you look at it as a relative change like 30 or 40% then it sounds really bad but a big change in a very small risk takes it from a very small number to a slightly bigger, but still very small number, so for most people the risk is very, very small. ‘People need to put it into perspective. This is a risk for certain age groups and that risk may have increased but for most people it is still not a serious disease.’