Covid infections have increased across all four nations of the UK, reaching record highs in Scotland, as a scientific adviser to the government warned of the need to “keep an eye on” the rising prevalence of the virus.
A total of 2.6 million people caught the disease in the week to 5 March, up from 2.4 million, according to new estimates from the Office for National Statistics.
It is the first time since the end of January that all nations have seen a simultaneous week-on-week increase in infections, and is the clearest indication yet that the virus is once again becoming more prevalent throughout the UK.
Professor Mike Tildesley, an infectious disease modeller and member of a Sage sub-group, said such increases were to be expected following the lifting of Covid restrictions, but warned that the situation needed to be monitored, adding that there was “early concern” at the recent uptick in hospital admissions in England.
However, he acknowledged that keeping “eye on” the growing prevalence of Covid is being hindered by the scaling back of testing and removal of the self-isolation mandate. Of the 2.6 million people estimated to have caught the virus last week, just 290,000 - or 10.9 per cent - of these infections were picked up and reported via the government’s Covid dashboard.
Prof Tildesley said the disparity was “stark” but “unsurprising”. He added: “We're not testing on the same level we were before and, of course, the isolation protocols are not in place as they were before. A lot of people are still isolating voluntarily but some people will not be doing that.
“So we aren’t necessarily going to see a significant resurgence in cases because, of course, people aren't testing. What you may see is what's going on in hospital. And that might be the first point that you start to see it now.
“Previously it was almost like clockwork. You saw a signal in cases. Then you saw a signal in hospital admissions, and then finally you saw a signal in deaths. Now, we're getting to the stage of almost removing that ability to see the signal in cases first, or certainly weakening that ability.”
For now, although each data release is seven days out of date, the ONS weekly Covid survey remains the most accurate and trusted method for determining the scale of the UK’s fluctuating epidemic in a post-restrictions world.
The rise in prevalence within England - around 2.1 million had Covid last week, up from 1.9 million - comes after three successive weeks of falling infections.
In the North West, East Midlands, West Midlands, East of England and London, the percentage of people testing positive increased in the week ending 5 March, the ONS said. The picture in the remaining regions of England was “uncertain,” it added.
By contrast Scotland has now seen infection levels rise for six weeks in a row, with 299,900 people likely to have had coronavirus last week, the equivalent of one in 18. This is the highest figure for Scotland since estimates began in autumn 2020. The previous record was 297,400 in the first week of this year.
Wales and Northern Ireland both saw a jump in prevalence last week following a period of falling infections, rising to 97,900 and 143,800 respectively.
The percentage of people testing positive has also increased in those aged 25 years and over in the week ending 5 March. Rates are falling in children under the age of 18.
Confirmation of the UK’s growing epidemic comes after data from the UK Health Security Agency (UKHSA) showed that hospital admissions also increased between 28 February and 6 March, with the highest rates reported in the South West of England.
“Early concern obviously is what's going on with hospitals, they are going back up now,” said Prof Tildesley. Admissions rates have increased among all age groups, but are highest among over-85s, at 118.8 per 100,000 people, up week-on-week from 88.8.
However, patient numbers remain well below the levels seen at the peak of the first and second wave of the virus, however.
Prof Tildesley added that it was difficult to predict whether the wider rising trends marked a “small resurgence” which will “calm down again”, or the beginning of a new wave.
“When you have a relaxation of restrictions and things are getting back to normal, you may get resurgences as a result of that, rather than as a result of your typical seasonal behaviour of viruses,” he said. “We may see a little bit of that through the spring and may get mini resurgences based upon different types of behaviour. The hope is that we don't get big waves going in over the summer.
“Again, we've got the vaccination status to think about as well. We've got potential for waving from boosters. But it’s all ifs, buts and maybes at this point. It’s too early to tell.”