#15,738
The aphorism, "An absence of evidence is not evidence of absence", holds particularly true when it comes to emerging infectious diseases, as it can take a long time to gather and analyse epidemiological data, and even then there are always multiple confounders that can muddy the waters.
Which explains why, after weeks of reassurances that there was `no evidence' that the B.1.1.7 (aka `UK') variant of COVID was any more severe than earlier variants, the UK government announced yesterday that there was a `realistic possibility' that B.1.1.7 is associated with a 30%-40% increased risk of death (see UK: NERVTAG paper on COVID-19 variant of concern B.1.1.7).
While a `realistic possibility' represents only a moderate level of confidence, there are enough early signals in the data to raise concerns. Since the NERVTAG (New and Emerging Respiratory Virus Threats Advisory Group ) report was released yesterday, a number of experts have weighed in on the Science Media Centre website.
For brevity, I've only excerpted 3 of the shorter opinions, so follow the link to read all of them (n=8 at the time of this post).As you might expect, given the preliminary nature of the data, there are a range of opinions.
JANUARY 22, 2021
expert reaction to suggestion made in Downing Street press conference that the new UK variant may be linked to higher mortality than the old variant (NERVTAG paper also now published)
Following an announcement made at the Downing Street press conference that the new UK variant, B.1.1.7, may be associated with higher mortality, a paper has been published by the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG).
Dr Leon Danon, Associate Professor in Infectious Disease Modelling and Data Analytics, University of Bristol, said:
“My group at the Universities of Exeter and Bristol looked at people tested in the community (Pillar 2 data). We performed a matched cohort study, where a person infected with the new UK variant was compared to a similar person (similar age, tested at a similar time, living in a similar area) infected with the old strain.
“We calculated the additional risk of death imparted by the new UK variant. We found that people infected with the new UK variant have an risk of death that increased by 50% – 170%. This means that, from our estimates, out of 1000 people infected with the new variant two would be expected to sadly die, compared with 1 person infected with the old variant.“Other groups using different approaches came up with slightly different numbers, but most suggest there is an increased risk of death with the new UK variant. The estimates depend on how well a given method is able to capture other, known risk factors. Ours is at the higher end of those estimates. The confidence intervals from the studies from other groups overlap with ours so the real answer is probably somewhere in the middle.”
Dr Simon Clarke, Associate Professor in Cellular Microbiology at the University of Reading, said:
“This is sobering news. The variant of the coronavirus which has swept across the UK is not only more transmissible, but appears to be 30-40% more lethal than those which we have previously experienced.
“Initial research indicates that the mutations found in the virus spike protein aren’t affecting the way antibodies respond to the presence of the coronavirus, blocking the entry of the virus into human cells.
“We don’t yet know whether the mutations in the spike protein or other parts of the coronavirus affect the ability of antibodies to tag the virus for destruction by white blood cells. Neither do we know the extent to which T cell immunity is affected.
“What we do know is that the variant is more able to bind to our cells, which could provoke a stronger overreaction by the immune system, which causes the worst disease, and can be fatal.”
All our previous output on this subject can be seen at this weblink:
