The Omicron coronavirus variant is the “most significant threat we’ve had since the start of the pandemic”, leading health chief Dr Jenny Harries has said.
The UK Health Security Agency (UKHSA) boss also warned that a wave of Omicron infections could put the NHS in “serious peril” as she defended the testing regime for travel.
Harries told the transport select committee that the UK was likely to see “staggering” case numbers of the variant — which now has a doubling time of under two days — in the coming days.
Harries told the Commons’ Transport Select Committee: “I’m sure for example, the numbers that we see on data over the next few days will be quite staggering compared to the rate of growth that we’ve seen in cases for previous variants.
“The real potential risk here – and I would underline that because we are still learning a lot about the variant – is in relation to its severity, clinical severity, and therefore whether those cases turn into severe disease, hospitalisations and deaths.
“We’re still at too early stage for that, in fact the world probably is still at too early stage to be clear.
“The difficulty is that the growth of this virus, it has a doubling time which is shortening – ie it’s doubling faster, growing faster.
“In most regions in the UK it is now under two days. When it started we were estimating about four or five.”
Scientists had “never seen a Covid-19 variant that’s capable of spreading so rapidly so we have to look at what we can do to slow omicron’s advance”, she told MPs.
“Trying to prevent ingress of any infections, including omicron, still remains a key point, particularly when we can foresee a very large wave of Omicron coming through and our health services potentially being in serious peril.”
According to the latest figures, there were 4,713 confirmed cases of omicron in the UK, but the UKHSA has estimated that the number of daily infections could stand at 200,000 a day.
From this morning the travel red list will be scrapped, meaning people travelling to the UK from the designated 11 countries in southern Africa will not have to quarantine in a hotel on their arrival.
However, any traveller aged 12 of over, regardless of their vaccination status, will have to take a pre-departure PCR test before arriving in the UK as well as PCR or lateral flow within two days of arrival.
Asked whether travel restrictions will help slow the spread of Omicron in the UK, Harries said: “I think travel restrictions have a time and place.
“I think what I’m sure committee members have seen this morning is, and I’m strongly supportive of this in public health terms, is that very early restrictions were placed on countries where we had good evidence of high rates of omicron at a time where we had low knowledge of rates in the UK, as a delaying tactic.
“That gives us time to prepare, to understand, to boost particularly our population, but actually it’s really important that where there isn’t a benefit, countries are clearly freed from those restrictions.
“At the moment the rate of growth in the UK, as I’ve just explained, is now significant, and the benefit of those border controls against particular countries is reduced.”
She added: “However, because we now have widespread global cases of Omicron there is still value in preventing that variant or other cases coming into the country when we don’t need it to be there, not least because we don’t want hospitals to be under any increased pressure than they are currently.”
Harries’ assessment comes amid stark warnings of what a wave of omicron infections could do to the NHS.
Graham Medley, professor of infectious disease modelling at the London School of Hygiene and Tropical Medicine, told BBC Radio 4’s Today programme that hospital admissions could reach 2,000 a day.
“I think it is a very real possibility that if the numbers of infections increasing continues in the way that it has done and it spills out into older age groups than we could see the number of people being omitted to hospital getting very large and certainly going over the thousand, maybe up to 2,000 a day,” he said.