"It is therefore highly likely that this variant is more transmissible than B.1.1.7 (high confidence), and it is a realistic possibility that it is as much as 50% more transmissible. ...
" ... There are also plausible biological reasons as to why some of the mutations present could make this variant more transmissible.
" ... It is unclear whether this same growth advantage that has been observed over recent weeks would apply to sustained wider community transmission regionally or nationally.
" ... The range of possible differences in transmissibility reflects the uncertainty around the number of imported cases, and the current relatively localised transmission.
This is another key paragraph
So, the Prime Minister has been informed (or could have been informed) that
"an even faster increase can be expected if measures are relaxed"
And this is also key. (But note the word 'if')
So, we don't know. But, *if* B.1.617.2 has a 40-50% transmission advantage vs. B.1.1.7, then it is likely that there would be a "substantial" resurgence of hospitalizations (similar to *or larger than* previous peaks)
It is clear that yesterday's SAGE meeting was significant.
The Prime Minister has taken the view that the risks of a possible substantial resurgence of hospitalisations - similar to or larger than previous peaks - is worth taking.
That is a political decision.
And here is the technical modelling analysis from SPI-M-O
SPI-M-O: "It is a realistic possibility that this scale of B.1.617.2 growth could lead to a very large increase in transmission. ...
"... At this point in the vaccine rollout, there are still too few adults vaccinated to prevent a significant resurgence that ultimately could put unsustainable pressure on the NHS, without non-pharmaceutical interventions"
"At the end of last year, as JCVI set out their priorities for who should be vaccinated, the first priority was to vaccinate those most at risk of dying. A secondary priority –one that can be overlooked– included the possibility of vaccinating those at increased risk of exposure.
“Since then, we now know that Covid vaccines can reduce transmission. This is great news, and together with the lockdown, cases have fallen significantly.
A quick overview thread of case rates prior to moving to Step 3 on 17 May.
Overall cases in the UK are at 21 cases per 100,000.
Case rates are higher than they were last summer after the first wave and before that unlocking.
Some of this is increase is due to mass testing.
In late June last year, cases in all age groups were under 10 cases per 100,000 (except 80+ where they were 12 per 100,000).
Cases now are higher.
If we compare to the extreme situation in January (seen below), things don't look too bad. If we compare to June last year, cases do look relatively high.
Most of these cases were related to travellers. We have since required quarantine for people that have been in India. So this should (in theory) reduce significantly the import of B.1.617.2