The headlines from today’s case data are concerning, and it’s certainly not great news. But there are some glimmers of hope in the detail by age, so let’s have a dig in. The overview doesn’t look too bad, with case rates stable in the under-40s, and still falling in the 40+ 🧵
But that is a slightly lagged view of what’s going on, and obscures some useful detail. So I’ve built some new graphs which break down each of those lines into 5-year age groups, with no averaging, and using data up to specimen date 9th Nov – NB this date will get revised up.
Here’s the under-20s, to start with – we can see growth re-emerging in the 5-9s and 10-14s, but not so much in the 15-19s. The 0-4s were already bouncing around, close to stability – and that looks to be continuing here.
The difficult question to answer is how high that growth in the 5-9s and 10-14s goes, and for how long. I’m not going to make a confident prediction, other than to note that I’d be very surprised if we returned to the kind of growth rates we saw in mid/late September.
On the other hand, a repeat of the smaller surge we saw in early/mid-October is very possible – but fortunately now starting from a lower base. This is easier to imagine using the raw case data (here for the 10-14s).
Now stepping up the age groups to the young adults, we can see roughly stable cases overall – although the recent declines in the 35-39s have been cut back in the last few days.
That pattern extends into the 40-60s, which also have returned from falling cases to near-stability. My sense is that this is more of a post-half-term back-to-work effect (rather than a sign of more infections from child to parent, which you’d expect to take a few more days)
There is slightly better news in the older adults, where declining cases are continuing – except maybe in the 60-65s who are more impacted by the back-to-work effect, and who mostly haven’t had their boosters yet. It would be good to see that happening soon.
And finally in the elderly, case declines continue – and in fact the rate of decline looks to be continuing to accelerate. Go boosters!
So overall, it feels there’s a good chance that cases in the 60+ will continue to decline, even as we see growth in some of the younger age groups. That’s not ideal (as there will be some inevitable leakage between the swimming pool lanes, and I’d still rather that kids…
…got vaccinated before they were infected). But it's definitely better that way round, and it may mean that the impact on hospitalisation statistics is more muted. We’ve already seen some decent falls in admissions this week, and I’m hoping that will continue.
Finally, the best news today was in the booster vaccinations, which jumped up; while some of that is catch-up from the last 2 days, the weekly run-rate is now over 2m per week in England, which is getting close to the level it needs to be at. /end
Honestly not a big fan of the case trends in the last couple of days. Here’s the overview: with the kids still driving the growth, but other groups also starting to pick up. (and I wouldn’t take too much cope from the flattening on the last day – that will get revised up) 🧵
Looking in more detail at the under-20s, we can see the power coming from the 5-9s, but with 0-4 and 10-14 not far behind, and even 15-19s now back into positive territory (i.e. cases growing)
The case trends remain hard to read, but with a bit of age-group case ratio analysis, I think we can see a bit further into the fog. Let’s start with the overview: cases still falling in the under-20s and over-60s, but not the 20-60s. But that hides some important detail. 🧵
Looking first at the older (60+) age groups., we can see some very steep (and welcome) declines in the 75+, a gentle decline in the 70-74s, and gentle increases in the 60-69s. Exactly what you might expect if we were giving boosters to the most elderly first, for example.
So – good news overall. But also a reminder that if we leave the 60-69s unboosted for too long, we might see those case rates drift upwards, which would be very unhelpful.
There been something bugging me for a while about how my model (and others) works. And I think I’ve finally pinned it down. It’s subtle and technical, but I think might turn out to be surprisingly important. And it’s all to do with the “leakiness” of the immunity model. 🧵
The difference between a “leaky” vaccine and an “all-or-nothing” vaccine has been well-covered by others – my favourite explanation is in this thread:
As it happens I’m not particularly happy with the “leaky” terminology – it could mean a number of different things, and so could be misinterpreted. I prefer to think about this in terms of the variability of the vaccine effectiveness (VE) at individual level.
I’ve been thinking a bit about optimism and pessimism, and how that might affect our views on whether additional restrictions (such as the government’s “Plan B”) should be imposed. It’s not quite as simple as it might first appear. Let me explain…. 🧵
The first thing to note is that optimism and pessimism can operate on different timescales. So you might think that things are going to get worse over the next couple of months, but that 2022 will be a more positive experience, due to boosters and improved treatments.
Or you might be relatively optimistic about the next couple of months, but concerned about the potential for a resurgence in early 2022 as we reach the depths of midwinter, and as waning immunity hits the populations in their 40s and 50s who may not have had a booster yet.
It’s been a while since we’ve had a set of SPI-M models and it’s taken me a few days to read through them properly. Having done so, I have a few thoughts – as usual I’ve found 10 key messages to take away. For reference, the papers are all here: gov.uk/government/col… 🧵
In terms of overall messages, I would agree with everything that @BristOliver said here:
. So I’ll focus my own comments more in the detail of how the modelling has been done, and its implications.
1) In general, the models are fairly optimistic about the course of the next 2 months, but after that they vary a lot – with some scenarios showing significant peaks in 2022 (at any time from January through to June) and others with no big resurgence
The news from today’s case data continues to be good, but because I can only do undiluted positivity for so long before providing some balance, I’m going to give you the good news quickly, and then give you four reasons to avoid premature celebrations.
First, the good news: case growth in school-age kids continues to decline, and even more quickly in the last day or two. (note: this latest cliff-edge is undoubtedly exaggerated by the impact of people doing fewer LFD tests last weekend, as half term started for most kids)
In particular we can see the 10-14s now clearly over a peak: (best to look at that orange dotted line, which is a 7-day centred average, for an indication of the trend)