The Implications of Omicron

(Disclaimer - below are my personal opinions only, not of an employer)

I wasn't going to do a post about this as (a) I'm on maternity leave and not that close to the data these days and (b) there are so many moving parts and wider considerations to take into account that I don't think anyone who really only has expertise in one area (ie infectious disease epi for me) can really comment on the "correct" course of action, - or even that there is a "correct" course of action, because whatever course of action is most beneficial/most harmful depends on what your personal circumstances are, making those decisions for an entire country even harder.

Still. My thoughts based on the evidence as we know it; not particularly detailed or referenced because I just don't have the time:

Omicron has got us worried because it's so transmissible, and because it has mutations which are associated with vaccine escape and potentially increased severity. Real-world data has confirmed that it's lots more transmissible than Delta, and that vaccines don't protect against it quite as well (at least if you've only had two doses), but severity indicators seem encouraging - at least if you have some pre-existing immunity, which most of us in the UK now have, thanks to both vaccines and natural infections (sometimes in combination!).

However, as we all know by now, a surge in infections - even if most have them mildly - can put pressure on the health service because even if a small proportion of people have severe illness, a small proportion of a very large number can still be a large number. And given how transmissible this variant is, we can expect (and are indeed seeing) a huge surge. It's going to be very, very hard to slow it down.

Where does that leave us? Well, this is where I get to the point that I don't feel qualified to answer really. The primary concerns seem to be over whether the NHS will cope with a surge in Covid cases, and I have no idea whether it can because that's not my area. However, what we do know is that South Africa coped very well with very high levels of Omicron without a parallel surge in hospitalisations, despite having a comparatively low vaccination rate. Part of that could be because they have a younger population, and because of "survivor bias" (a nice way of saying that those vulnerable to Covid will have already died in earlier waves). But still, it's encouraging.

There's been a clamour for further restrictions and calls for lockdowns, but they don't sit comfortably with me for several reasons.

Firstly, lockdowns have huge wider public health harms that are harder to see than rising hospital numbers, but nonetheless awful - people lose jobs, children get abused, mental health plummets etc. Even the pressures on the health service are in large part due to past restrictions, e.g. postponed surgeries etc. Lockdowns should never be a "reach for" tool in infectious disease control unless we're facing an absolute calamity in my opinion - indeed, in all of my training I never heard of the term until Covid. (See also: border controls - never in my life would I have predicted these cruel and largely ineffectual measures being so easily reached for as a tool to control infections).

Secondly, lockdowns don't so much solve the problem as just put it on pause for a while - fine when in lockdown 1 we used the time to improve testing, surveillance, healthcare preparedness etc, and in lockdown 2 when we were waiting for vaccinations. But winter is going to last a long time, and what's the exit plan? We could even potentially shoot ourselves in the foot by locking down for a period, allowing more time to elapse between having boosted the most vulnerable, and re-opening when their immunity from boosting has begun to wane. Indeed, some modelling has suggested that a lockdown now would lead to a larger exit wave than if we don't.

Thirdly, I worry for what lockdowns and tight restrictions will do for compliance with vaccination in future - which is still our best tool in our defence against Covid. Why would people continue to go to get vaccinated if we're going to curtail their basic freedoms anyway? Even if a lockdown prevented a big disaster - how would we actually convince people of that? We'd see the perennial problem in public health of the perception being "I got vaccinated, they took away my freedoms anyway, and there wasn't even a big wave like they said there would be". We have to tread really, really carefully here I think.

My worries about Omicron are more that the measures we have till now been using are no longer fit for purpose. For example, Test and Trace will not stop chains of transmission if by the time you've got a PCR back and phoned someone's contacts, their period of potential infectiousness has come and gone - which is much more likely given how fast Omicron spreads. In addition, I worry about the impact on society functioning if we see lots and lots of people isolating and unable to go to work for what will essentially be a mild illness for many.

To me, it feels like Omicron may be a point where we need to reassess what we're doing to combat Covid, and to move to a place where we rely primarily on boosting vaccinations (to reduce the possibility of severe disease) and to make much more judicious use of LFTs (to reduce the number of infectious people being out and about). Even last week this would have seemed a heretical thing to state in an environment when so many public health people seemed to be calling for LOCKDOWN NOW - and it is a scary thing to publicly oppose as the consequences of getting this wrong and there being another huge wave of mortality in January would obviously be awful - but the emerging data still seem to be encouraging and I still believe that a lockdown now would do more harm than good.

However, heretical though it may have been, it seems someone somewhere may have been thinking along those lines because we now see the rules being changed e.g. the isolation period for cases being reduced from 10 to 7 days if you have two LFT consecutive negatives 24 hours apart; and vaccinated contacts not having to isolate but to take daily LFTs instead etc. I wonder whether we will see the requirement for PCR confirmations dropped soon enough.

BOTTOM LINE: best things we can all do in the light of Omicron -

*GET BOOSTED - all signs are good that this will very much reduce your risk of severe illness, and (although to a lesser degree) getting infected/transmitting the infection

*LFTs -
(a) if you're going to be mixing, especially if in an indoor closed environment or with someone who's vulnerable, do an LFT *just before you leave the house*. Omicron moves fast so the "within 48 hours" rule of thumb no longer applies; you can turn from negative to positive very rapidly

(b) if you have cold-like symptoms, test yourself *daily* - one negative test at the beginning of your illness doesn't rule out Covid

*VENTILATE - all respiratory infectious love a closed and stuffy environemnt, so get that air circulating

As a bonus, if you're vulnerable and worried about catching Covid

*WEAR A GOOD MASK - ie FFP2/FFP3/N95 that fits well to prevent you getting infected. There isn't a good quality evidence to suggest that cloth masks do much to prevent transmission actually, so although there are mask mandates in place do not rely on them to keep you safe. In my opinion, those mandates are more about appearing to be doing something than they are actually effective in slowing the spread of infection, and probably risk the danger of giving a false sense of security for many people. Quite possibly an intervention that may, in the fullness of time, prove to have done more harm than good.

So those are my professional opinions; they are opinions and not gospel and I'm sure I have colleagues who would vehemently disagree with me on some, if not all, of it. It'll be interesting to see how well this post ages when I look back in my Facebook memories!

Merry Christmas, all.