02-02-21 07:22:00, SARS-CoV-2 N501 mutation lineages (nextstrain.org)
A brief update on the new coronavirus mutations, including the ‘British’, ‘South African’ and ‘Brazilian’ variants (i.e. N501Y.V1-V3), and evidence of their properties:
- There is currently no evidence that new variants are more virulent or lethal or produce any different symptoms. The fact that covid is generally more severe in winter than in summer and spring was to be expected (e.g. due to much lower vitamin D levels).
- There is currently no solid evidence that new variants are intrinsically more contagious or infectious, and suspected higher viral loads have already been disproven. The fact that transmission is higher in winter than in summer and spring was to be expected.
- In several regions of England, the percentage of the new variant is already decreasing.
- There is also currently no evidence that new variants preferentially infect children.
- There is no evidence that measures such as lockdowns or face masks work any better or any worse against the new variants. Several places affected by new variants have already seen a drop in new infections (e.g. Denmark, Switzerland and the UK itself).
- The fact that ACE2 receptor affinity is higher in new variants does not mean that their virulence or infectiousness must be higher; they may as well be lower or unchanged.
- The fact that a new variant is partially replacing an older variant does not require higher intrinsic contagiousness or infectiousness. This effect is well known from previous Sars-Cov-2 variants (e.g. D614G and the ‘Spanish variant’) and also from seasonal influenza viruses.
- The fact that places with a small first wave are seeing a much stronger second wave (e.g. Portugal and Denmark) was to be expected and does not depend on new variants – e.g. Ireland, Eastern Europe and Uruguay all saw stronger second waves of the original variant.
- There is, however, clear evidence of partial immune evasion of new variants,