The latest on England's big JN.1 Covid wave - unlikely to have peaked yet...

As we went into Christmas 2023, the ONS Winter Infection Survey (based on thousands people testing on lateral flow tests regardless of symptoms) showed that we were in the biggest wave England had seen since the summer of 2022. Neither the ONS survey nor the UKHSA published data updates over the Christmas period, but we do have some new information to inform what might happen over the next few weeks.

The latest variant data from England shows that JN.1 (the new fast spreading Omicron subvariant) is now dominant in England at 52% of sequenced cases as of 23 December 2023. We last experienced waves like this in 2022, so can we learn anything about when this wave will peak? Looking back at variant and prevalence data from then, we can see that infections peaked between 3 and 4 weeks after a new variant reached dominance at 50% of sequenced cases.

We also know that hospital admissions with recorded Covid did continue to increase in the week before Christmas (before JN.1 reached dominance).

My best guess would be then that this JN.1 wave will peak towards the end of next week about 3 weeks after it reached dominance, but it might be pushed a bit later because of the impact of Christmas and New Year mixing and then a return to work and education in early January.

That said, things are not directly comparable now to two years ago. On the one hand, in early 2022 we had Plan B (e.g. work from home where possible & masking) during the first Omicron wave, far more recent vaccinations for most (the autumn/winter 2021/2022 booster campaign), freely available Covid tests (till March 2022) and higher general awareness about Covid. All these would have dampened transmission two years ago and we do not have any of them now. On the other hand, we have far more (sadly) immunity from previous infections in the population now and another 3 booster doses for our most vulnerable, and that will have a dampening effect now.

My personal feeling is that this wave will be as high as the large waves of 2022, and possibly even the highest so far, in terms of infections, but that hospitalisations with Covid will not reach the highs of 2022 (and will be nowhere near the highs of the pre vaccination Covid waves). That doesn’t mean it’s ok though. High infections will cause short term work disruption as people are off sick, and result in thousands developing new Long Covid. Meanwhile, higher hospital admissions are obviously bad for those sick enough to need hospital care, and will also strain NHS capacity as flu is also likely to peak this month.

We do have a way to reduce hospital admissions and that’s an anti-viral drug called Paxlovid which you take as soon as you know you’re infected and which is proven to reduce your chance of severe illness, even with newer variants. However, its use is extremely restricted in the UK and many other European countries compared to elsewhere (in the US for instance, it’s available on prescription to many more people) and Europe is now facing throwing away one to two billion dollars worth of Paxlovid stock becaust it’s expired.

I hope this latest large wave will prompt a reconsideration of how we “live with Covid”. Firstly, making the most of the medical interventions available with increased access to anti-viral medications and to vaccine boosters (plus investing in next generation vaccines). Secondly, a renewed investment in reducing transmission through cleaner indoor air (which does not restrict anyone’s ‘freedom’ and works against all airborne diseases) and reminding people about well fitting, high quality masks during waves, especially in hospitals and care homes. Finally, be careful out there over the next few weeks!