In addition to 10 instances now also confirmed in Scotland, the UK’s total currently stands at 32, with Wales and Northern Ireland yet to record a single case of the new strain.
The nine cases on Wednesday were found in London, the southeast, the northwest, the east Midlands and the east of England, according to UKHSA.
Those who tested positive and their contacts are already isolating, the agency added, with investigations underway to establish if there are any links to travel to southern Africa – as with previous cases.
Dr Jenny Harries, chief executive of UKHSA, said in a statement: “It is very likely that we will find more cases over the coming days, as we are seeing in other countries globally and as we increase case detection through focused contact tracing.
“That’s why it’s critical that anyone with Covid-19 symptoms isolates and gets a PCR test immediately.”
Vaccines and public health minister Maggie Throup issued a similar warning yesterday, telling MPs in the House of Commons officials were expecting to find further cases of omicron “in the coming days”.
So far, infections have been confirmed in the London boroughs of Barnet, Bexley, Camden, Haringey, Lewisham, Newham, Sutton, Wandsworth and Westminster.
Outside of the capital, cases have been recorded in the local authority areas of Brentwood, Buckinghamshire, Lancaster, Liverpool, North Norfolk, Nottingham, South Cambridgeshire and Three Rivers, data shows.
Dr Harries, of UKHSA, clashed with the government on Tuesday, after advising the public that “being careful, not socialising when we don’t particularly need to” and having a booster jab were important steps in reducing the spread of the omicron variant.
Boris Johnson, on the other hand, urged the public not to scrap social plans in the run-up to Christmas – on the same day he tightened Britain’s border controls and made face masks a mandatory requirement in shops and other public spaces once more.
The PM’s spokesman said earlier there is “nothing to suggest” younger people are worse affected by the new variant, when asked about new reports coming out of South Africa, where it is believed the strain originated.
Following reports from Tshwane, in South Africa, that children under the age of two accounted for about 10 per cent of total hospital admissions with the variant, the spokesman told reporters “there’s no hard evidence to suggest [omicron] disproportionately affects children”.
“Clearly, we will [be] monitoring all evidence very carefully,” he added. “It’s important to stress that there is nothing to suggest it’s impacting on different age groups in a different way to [what] we see with other variants.”
Meanwhile, the World Health Organisation (WHO) said early indications suggest the majority of omicron cases reported so far in at least 23 countries have been “mild”.
Though the agency did stress there is still a lot of information yet to be discovered about the new strain, as scientists around the world race to find out what they can about its transmissibility and potential deadliness.
“WHO takes this development extremely seriously, and so should every country,” director-general Tedros Adhanom Ghebreyesus said in a press briefing. “But it should not surprise us, this is what viruses do.”
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