Experts believe the increased prevalence in the two regions – which has seen the capital, and large parts of Essex put into Tier 3 in recent days – may be linked to key mutations detected in the strain. Professor Nick Loman, from the Institute of Microbiology and Infection at the University of Birmingham, a member of the COVID-19 Genomics UK consortium (COG-UK) said: “There is actually 17 changes that would affect the protein structure in some way that distinguish this variant from its kind of common ancestor of other variants that are circulating, which is a lot.
“It’s striking. There’s a really long branch going back to the common ancestor, and it’s a matter of great interest as to why that is the case.
“Intriguingly, there no indication the strain had evolved in another country and arrived in the UK, Prof Loman said, admitting: “It’s sort of come out of nowhere.
“We have a long gap between the first cases we saw with this variant in late September.
“It’s more likely to have evolved in the UK but we don’t know that.
“There are very few examples of this variant in other countries at the moment – it’s really a kind of UK phenomenon.”
Health Secretary Matt Hancock mentioned the new strain in the House of Commons this week.
Many of the changes relate to the virus’s spike protein, which enables it to latch onto human cells and cause illness.
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In a statement issued yesterday, COG-UK said: “Efforts are under way to confirm whether or not any of these mutations are contributing to increased transmission.
“There is currently no evidence that this variant (or any other studied to date) has any impact on disease severity, or that it will render vaccines less effective, although both questions require further studies performed at pace.
“We will provide further updates as our investigations proceed.”
The statement added: “COG-UK has developed a Summary Mutation Report, which will be released online each week as a companion to the Coverage Report.
“The first prototype will be released by 18th December, with improvements made over time.
“This will focus on mutations that are common, and/or are of existing or emerging interest.
“These reports will be caveated since they represent a subset of true case numbers.”
In Basildon in the week ending December 11, the case rate was the third-highest in England, standing at 696.1 cases per 100,000 people, a rise of almost 300 on the week before.
In neighbouring Thurrock, the figure was 506.5, more than double the previous week’s total of 236.9, and in Epping Forest it was 501.2, compared with 233.1 the previous week.
The number of cases is currently outstripping those in London, where the highest figure – Havering, which borders Essex – is 506.3 over the same period.
The rate for England as a whole is 172.8.
