The government's New and Emerging Respiratory Virus Threats Advisory Group (Nervtag) has concluded that the new Covid-19 strain may be a bit more lethal than the original strain.
I've spoken to the influential Nervtag member, Prof Neil Ferguson about this.
He has given me this statement: "It is a realistic possibility that the new UK variant increases the risk of death, but there is considerable remaining uncertainty.
"Four groups - Imperial, LSHTM, PHE and Exeter - have looked at the relationship between people testing positive for the variant vs old strains and the risk of death - that suggests a 1.3-fold increased risk of death.
"So for 60 year-olds, 13 in 1000 might die compared with 10 in 1000 for old strains.
"The big caveat is that we only know which strain people were infected with for about 8% of deaths.
"Only about 25% of people who eventually die from Covid-19 get a pillar 2 test before they are hospitalised (at which point they get a pillar 1 test, but pillar 1 tests don’t tell us which strain they were infected with).
"And we can only distinguish the new variant from the old variant for about 1/3 of pillar 2 tests.
"All that said, the signal is there and is consistent across different age groups, regions and ethnicities."
The worrying news is that although treatments for Covid-19 have improved, the new strain does seem to be more lethal.
I understand Chief Scientific Adviser Sir Patrick Vallance will address this issue at the press conference with Prime Minister Boris Johnson on Friday evening.
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