Thread by @ewanbirney

A Coronavirus view from London and Europe: TL;DR The Omicron storm is hard for healthcare management in the UK, but less deadly than feared; London leads the UK out with many indicators dropping; Is the UK experience going to replicate elsewhere?

Context: I am an expert in human genetics and computational biology. I know experts in infectious epidemiology, viral genomics, public health and clinical trials. I have some COIs - I am consultant and shareholder to Oxford Nanopore and was on the Ox/Az trial.

Key recap; the latest substantially different in biology variant of SARS-CoV-2, Omicron, will infect on top of previous SARS-CoV-2 infection and on top of double vaccination; triple vaccination less so.

Omicron causes different symptoms, replicates in different places in the airways and, at least for people with previous infection (often the case in South Africa) or at least double vaccination (often the case in UK) an infection is less likely to lead to ICU admission.

Omicron's immune invasion and eye-wateringly fast transmission means it moves very fast through populations - all countries have it. This fast transmission places a different type of stress on healthcare than the earlier waves.

Firstly there are many people with milder COVID or asymptomatic infection and another ailment in hospital, but these people *still must be treated in infection-control wards*. Hospitals are (unsurprisingly) enriched in at risk people with poor health, so infection control is key.

Secondly good management of the infection means many healthcare workers must be kept out if infected and/or risk of infection if close contact. This reduction in staff numbers makes dealing with this complex rush hard.

These are different stresses, but very real stresses on hospitals, and key to prevent more harm (infected people in a moment of poor health is exactly how to cause more harm). Although the individual risk is far lower, the system risk is different and high.

I know colleagues in the NHS, and they seem broadly like they are coping, but I am not an expert or know experts in hospital stress/workforce management etc. Like a lot of the UK COVID twitter, I rely on @ChrisCEOHopson as an active barometer on this.

London has turned in virtually all indicators (though the resumption of school might upset all of that); North West is plateauing on admissions, and North East looks like it might have the highest peak in this wave.

Looking beyond UK many places in Europe, such as Denmark, France, Italy, Spain, Portgual and Republic of Ireland are broadly going for the same "flatten the curve somewhat, but accept most people will be exposed, many infected".

I personally think the key metric here is triple vaccination levels >60; this will I think be "at risk" people for hospitalisation, and if this is too big, flattening curves wont be able to impedence match the exponential growth of cases wrt fixed/linearly scaleable healthcare

Here if the UK can get through this Jan, so should Portgual, Spain, Denmark, Ireland. By the aggregate numbers UK and France's vaccination are v. similar, but France has a bigger gap in the older ages (UK's gap in the younger). France's healthcare has more capacity though.

(though if I am not an expert on UK Healthcare operations I am even less informed on French! But this is what I pick up).

The other aspect is not to forget about Delta; both in the US and in South East France, a fair bit of the current hospitalisation and ICU is Delta continuing to grow, in some ways hidden by the huge Omicron case numbers.

Netherlands and Germany are in a somewhat different position; their control of Delta (which broadly worked in both places, with the usual aspects of reducing life/economy) merged into controlling Omicron but now cases are rising again, driven by Omicron

(Asides: One for the transmission officiandos is that the relative growth of Omicron in Germany vs Delta has been less than in the UK; basic hypothesis is that the shorter generation time of Omicron makes NPIs (eg, FFP2 mask wearing) more effective.

The other endless conundrum is that in the UK there is some "smudging" of the top of infection curves locally - falling off exponential growth at higher case levels. I personally think this a feedback loop of local cases and free+easy testing in the UK (this has worked well)

In Germany the Omicron rise is in the cities (eg, Hamburg + Berlin) and the west. Even the usually best-in-class Schleswig-Holstein has high case levels. The German East (former East Germany) is about 1 or 2 weeks behind.

However, Germany has an even bigger older vaccination gap, in particular in former East German states (Saxony and Thuringia). Closing this gap is key, and I personally think more engagement (door to door?) and carrots (vouchers?) rather than sticks (mandates)

This gap is also present in Austria, which has a similar problem of how to close that gap or somehow navigate Omicron's hopsitalisation flows. Netherlands booster campaign was slower than much of the rest of Europe last autumn so they have play catch up.

I am ... broadly hopeful (as ever) and we're shifting phases, but the fact we're shifting doesn't make it *easy* to do (in particular, to stress, in healthcare delivery in this) and we've got plenty of things that can still go against us.

However, I do think 2022 will be better than 2021.