Thread by @BillHanage

So growth rate and R number in the UK now over 1. Unsurprisingly given that Delta variant now dominant. A short thread on the next few weeks there, which will be (sorry) big on uncertainty gov.uk/guidance/the-r… 1/n

That's quite a large increase. The caveat of course is that it is from a *very* low base indeed. And cases will not necessarily translate into severe illness, especially in vaccinated people 2/n

Unfortunately these too are up, from a low baseline. This should be treated with caution because when numbers are this low they can be impacted by unusual events like clusters of infection in vulnerable populations - although you'd hope such folks were vaccinated 3/n

This is a good total with one dose. But by my math that's nearly 60% not fully vaccinated, and 40% not at all. ~20% with one dose, which provides poor protection against symptomatic infection with the Delta variant. Several questions there... 4/n

What about vaccine specific efficacy of single dose? ie Pfizer vs AZ? What about breakdown by age (older and younger more likely to get Pfizer)? Crucially, what do vaccines, one dose or two, do to protect against serious illness due to Delta? I don't know the answer 5/n

I am certain the coming weeks will see more cases. What that means for severe illness, deaths and stress to healthcare in the UK will depend on the answer to my previous question. My opinion is that vaccines will still do a lot to help, exactly how much remains to be seen 6/n

We are in for a tense few weeks waiting to see what emerges. But we're not going to find out overnight. Sorry, I warned you there would be uncertainty. This might end up being anything from a bit bad but basically OK to really quite bad ('quite' in the US sense of 'very') 7/n

As it is the majority of the virus population in the UK is a more transmissible, probably more virulent variant that shows evasion of vaccine induced immunity from a single dose and *60%* of the population has received one or no doses of vaccine assets.publishing.service.gov.uk/government/upl… 8/n

And for goodness sakes think about the many people who do not live in the UK (or US) and who are still awaiting any hope of vaccination at all. Delta is bad, but whatever happens in the UK won't be as bad as it might have been. Won't be as good either but that ship sailed 9/end