Coronavirus cases in the UK are rebounding, driven by a jump in infections among schoolchildren, according to a major symptom tracker study, as the Omicron subvariant BA.2 shows early signs of being able to outcompete the original variant.
There were 159,586 new daily symptomatic Covid-19 cases across the UK on January 24, according to estimates from the UK’s Zoe symptom tracking app, up 10 per cent from the 144,527 cases reported a week earlier. Case numbers had peaked at nearly 210,000 in early January.
The uptick in cases was driven by a fast-rising infection rate among under-18s which “has accelerated, to its highest level”, the study noted. Cases are also “spilling over” into their parents’ age group, with infections also increasing among people aged between 35 and 55 years old.
The new data come as England on Thursday dropped the last of its plan B measures of compulsory mask-wearing in shops and on public transport and requiring vaccine passports for large events.
Tim Spector, professor of genetic epidemiology at King’s College London who leads the study, said: “The bounce back in case numbers just as we lift restrictions has come sooner than many expected.”
He pinned the uptick on the return of schools after the holidays, ushering in a “rapid rise” in cases among children which then “cross over” into parents and school staff.
Spector also warned that “another emerging factor” in the jump in cases was the Omicron subvariant BA.2, which he said was “likely more infectious” than the original. Last week, the UK Health Security Agency designated the subtype a “variant under investigation”, citing “increased growth rate” over the earlier form of Omicron.
In the UK, the subvariant accounted for 1 per cent of genomically sequenced cases uploaded to the global repository Gisaid in the week to January 23, up from just 0.5 per cent the week before.
In Denmark and India, BA.2 already makes up about half of all sequenced cases, according to Gisaid.
Denmark’s Statens Serum Institut on Wednesday said preliminary calculations indicated that BA.2 had a 50 per cent transmission advantage over the original Omicron variant, BA.1, but it was no more likely to result in hospitalisation.
Spector predicted infections would “stay high until spring”. “It’s clear that Covid and its new variants will continue to have an impact on our day-to-day lives for some time,” he added.
Meanwhile, new data from NHS England published on Thursday revealed that staffing shortages in hospitals prompted by the Omicron wave were continuing to abate.
About 23,770 staff were absent due to Covid illness or isolation across England’s 137 acute hospital trusts as of January 23, a decrease of 53 per cent from the peak of nearly 50,000 absences recorded in early January. In total, about 68,000 NHS staff were absent on January 23 due to all reasons.
Matthew Taylor, chief executive of NHS Confederation, which represents organisations across the healthcare sector, said the improvement in staff sickness rates was “encouraging”. However, he said the NHS was still “coming under real strain” because of “very full” hospital wards.