A UK-wide lockdown to deal with the threat of the Omicron variant of coronavirus cannot be ruled out, although the current threat is unclear, a member of the Scientific Advisory Group for Emergencies (Sage) has said.
Professor Neil Ferguson, from Imperial College London, whose data was instrumental to the UK going into lockdown in March 2020, said the variant is concerning but it is still unknown what its impact will be on severe disease.
It came as Dr Mike Ryan, from the World Health Organisation (WHO), told the AFP news agency that existing Covid-19 vaccines should still protect people who contract Omicron from severe illness.
He also said initial data suggests that Omicron does not make people sicker than Delta and other strains. “If anything, the direction is towards less severity,” he said.
Earlier, Prof Ferguson suggested people may be told to work from home in the near future as Omicron is spreading fast, with the variant set to take over from the Delta strain before Christmas.
Speaking in a personal capacity, he told BBC Radio 4’s Today programme: “Certainly case numbers of Omicron are doubling at least every three days, maybe even every two days at the moment, so it’s accelerating very fast and, (to) put that in context, it’s the same if not faster than we saw with the original strain of the virus in March of last year. So it is a concern.
“It’s likely to overtake Delta before Christmas at this rate, precisely when is hard to say.
“We’ll start seeing an impact on overall case numbers – it’s still probably only 2%, 3% of all cases so it’s kind of swamped, but within a week or two, we’ll start seeing overall case numbers accelerate quite markedly as well.”
Prof Ferguson said the peak of this wave of infection will be in January if no measures are taken to slow it down.
“So if you don’t do anything at the current time, it will most likely be some time in January,” he said.
“But I think the key question is whether the country decides to adopt measures to either slow it down or try to stop it, and that will critically depend on really the threat it poses in terms of hospitalisations.
“At the moment, we don’t really have a good handle on the severity of this virus; there’s a little hint in the UK data that infections are a little bit more likely to be asymptomatic, but we really need to firm up that evidence at the current time.”
Asked whether people should be told to work from home, he said: “It will be up to the Government to decide what to announce in the coming days and weeks.
“There is a rationale, just epidemiologically, to try and slow this down, to buy us more time principally to get boosters into people’s arms, because we do think people who are boosted will have the best level of protection possible, but also to buy us more time to really better characterise the threat.
“So, if you imagine a kind of Plan B Plus with working from home might slow it down – it wouldn’t stop it but it could slow it down, so it’s doubling rather than every two or three days, every five or six days.
“That doesn’t seem like a lot, but it actually is potentially a lot in terms of allowing us to characterise this virus better and boost population immunity.”
Regarding lockdowns, Prof Ferguson said it is very difficult to rule out anything, adding that we “haven’t got a good enough handle on the threat”.
He added: “Clearly, if the consensus is it is highly likely that the NHS is going to be overwhelmed then it will be for the Government to decide what what he wants to do about that, but it’s a difficult situation to be in of course.”
Pushed on whether lockdowns might be possible, he said: “It certainly might be possible at the current time.”
Earlier, Prof Ferguson pointed to a new lab-based study from South Africa suggesting the Pfizer vaccine works less well against Omicron.
He added: “There’s a little bit of preliminary work even from the UK which suggests if you’ve had two doses, for instance of Pfizer, then just protection against mild disease may be roughly halved.
“But we think that protection against severe disease is much more likely to be maintained at the high level, but we don’t have firm data on that. That’s just based on extrapolation from past experience.”
The professor also said that visitors travelling to Scotland for the Cop26 climate change conference last month may have caused early seeding there, but added that this is “speculation”.
It comes as Health Secretary Sajid Javid pulled out of a key broadcast interview with the Today programme following the emergence of leaked footage showing Government aides joking about a festive gathering last year.
In footage obtained by ITV News and released on Tuesday, the Prime Minister’s then-press secretary Allegra Stratton and adviser Ed Oldfield, along with other aides, were filmed laughing about a “fictional” Downing Street party in December 2020.
Meanwhile, the new study on Omicron from South Africa suggests it appears to reduce the effectiveness of the Pfizer vaccine, though experts said a booster shot could help.
The study, which has been published online but not peer-reviewed, found that antibodies produced by vaccinated people are less good at keeping the Omicron variant from infecting cells than other forms of the coronavirus.
While some experts said the data is concerning, it only covered one part of the immune system and did not look at T cell immunity, which is thought to play a role in longer-term protection.
Researchers at the Africa Health Research Institute in Durban used a lab study to look at the effect of Pfizer on Omicron and found about a 40-fold reduction in levels of neutralising antibodies produced by people who had received two doses of the PfizerBioNTech vaccine, compared with the original Wuhan strain of the virus.
Professor Alex Sigal, a virologist at the Africa Health Research Institute, who led the research, told reporters: “While I think there’s going to be a lot of infection, I’m not sure this is going to translate into systems collapsing.
“My guess is that it’ll be under control.”
Prof Sigal also tweeted on Tuesday night: “Just be be clear on something… this was better than I expected of Omicron.”