How much risk can PM take with omicron to avoid ruining Christmas?

‘Urgent questions remain regarding whether omicron is able to evade vaccineinduced immunity’

‘A variant that’s 50 per cent more transmissible would in general be a much bigger problem than a variant that’s 50 per cent more deadly’

Judging from my mailbox, there is really only one Covid question on people’s minds at the moment: will omicron ruin Christmas? Well, that and various technical questions about the appropriateness or otherwise of “consensual stranger snogging”.

What people want to know is: will there be another lockdown; will the Prime Minister suddenly lunge from Plan A to Plan C in an 11th-hour bid to “save the NHS” as he has done twice before?

Already, over-75s have been asked to help save their GPs by staying away from routine appointments.

The data on omicron emerging from South Africa provide some important pointers but not the answer. They show the variant is spreading rapidly in the community there, with cases up from around 300 three weeks ago to nearly 7,000 today on a seven-day average.

The pattern is the same in several regions of the country, which suggests that it is something inherent to the virus that is driving it, rather than a local oddity in the environment or people’s behaviour.

It is clear, too, that large numbers of people who have had Covid are being reinfected. “Population-level evidence suggests that the omicron variant is associated with substantial ability to evade immunity from prior infection,” noted a study published on Thursday.

“Urgent questions remain regarding whether omicron is also able to evade vaccine-induced immunity, and the potential implications of reduced immunity to infection on protection against severe disease and death.”

Last week, GPs in South Africa were seeing many “mild” cases of Covid they believe to be caused by omicron. This remains the case, but the new variant, just like the others before it, can also cause serious disease.

This is evident from hospital admissions in Gauteng, which have been rising faster than in any previous wave (see chart). Over the past week, there have been over 1,000 hospital admissions in the province, nearly quadruple the number recorded two weeks ago.

Prof Rudo Mathivha, an intensive care specialist, painted a grim picture from inside Chris Hani Baragwanath Academic Hospital, in the vast Soweto township on the outskirts of Johannesburg.

“A 15-year-old died this morning. He was a new Covid-19 admission and developed pneumonia,” Prof Mathivha said on Friday. “We shouldn’t be seeing these kinds of numbers this early in the wave. We should not be seeing a young child who is moderate to severely symptomatic needing supplementary oxygen or high-care intervention. It is this which is worrying me.”

The alpha and delta variants turned out to be more deadly than the original Wuhan virus. We will find out eventually if the same is true of omicron but it will take much more data and time.

The next big news item around omicron will almost certainly centre on its ability or otherwise to evade vaccine-induced antibodies in laboratory tests. Scientists have been working on this in labs around the world for more than a week now and we can expect the first results shortly.

Initial headlines are unlikely to be good. Most experts think the virus will evade vaccine-induced antibodies in the lab. Indeed, the UK Health Security Agency’s latest risk assessment already puts omicron in the red zone for “vaccine acquired immunity”.

But as Dr Muge Cevik, an infectious disease expert at the University of St Andrews, points out, lab tests are far from conclusive as far as human immunity is concerned. Omicron may evade antibodies in test tubes but vaccine-induced T-cells could still protect us.

“While [antibody] studies will likely give worrying results, once we start to get some real-world studies into how things are doing, my guess is that vaccines will still be doing a decent job in protecting people from getting sick,” she said.

The UK is much better vaccinated than South Africa where just 25 per cent of the population is fully jabbed.

Another positive is that omicron may not spread as quickly when up against delta, the dominant variant in the UK. But this seems a forlorn hope if the variant is able to reinfect people in Britain at the same rate it is reinfecting South Africans.

“If, as appears increasingly likely, omicron can infect people that other variants can’t, then it will grow very quickly,” tweeted Graham Medley, head of the Government’s SPI-M modelling group yesterday.

So what does all this mean for Christmas?

If I was forced to bet on it (never a good idea), I would guess that omicron will spread rapidly in the UK but will not, for the most part, cause serious disease in those who are fully vaccinated and boosted. To put a time frame on this, I would go with Trevor Bedford, a virologist at the Fred Hutchinson Cancer Research Center in Seattle, who calculates it takes about eight weeks from arrival for omicron to visibly manifest itself as an epidemic.

For the UK, that would take us to mid to late January, which avoids Christmas. But before you get the party crackers out, consider two important facts.

First, in the words of the epidemiologist, Adam Kucharski: “A SARS-CoV-2 variant that’s 50 per cent more transmissible would in general be a much bigger problem than a variant that’s 50 per cent more deadly.”

This is a simple matter of maths: more infections mean more hospitalisations.

“Emerging evidence suggests omicron spreads easily. So even if immunity against severe disease fully holds up, countries could face a much faster, larger peak than delta would have caused”, notes Prof Kucharski.

It is in this context the Prime Minister will have to consider the NHS and the risk of it being overwhelmed.

Admissions have come down in recent weeks but are flatlining, with 7,373 Covid cases in UK hospitals, including 895 in intensive care. The system continues to run hot – with the worst weeks of January still to come.

Cases are climbing from a low base but there is community transmission. If they follow South Africa’s trajectory they will grow quickly.

Ultimately, the question for the Prime Minister is: how much of that growth – and therefore risk – can he and the NHS tolerate?