Cases of the Indian variant of coronavirus are continuing to spread rapidly across the UK.
The number of people testing positive for the variant leapt by 2,111 to 3,424 in the space of a week, according to data released by Public Health England (PHE) on Thursday.
In England, 151 local authority areas have identified at least one case of the Indian variant, according to figures from the Wellcome Sanger Institute.
Most of the country's cases are concentrated in areas in the North West and in London, with Bolton reporting the highest overall numbers of cases.
Rising cases of the Indian variant in England's four worst hit areas
These are the 10 areas with the highest number of cases in the week to 15 May, the most recent date for which full data is available.
Bolton – 611
Blackburn with Darwen – 145
Bedford – 126
Leicester – 64
Wigan – 57
Manchester – 50
Nottingham – 41
Sefton – 40
Central Bedfordshire – 40
Greenwich – 37
The variant now accounts for 37.2% of cases in England, and is expected to become dominant in the UK, according to England's chief medical officer Professor Chris Whitty.
Ministers were accused of incompetence on Tuesday after it emerged that guidance urging people in Indian variant hotspots to restrict their socialising and travel was slipped out last week.
Watch: Shadow minister says government advice has been ‘appalling’ for Indian variant hotspots
Health chiefs and MPs for the eight areas have said they were not consulted – or even informed – about the new advice, which was published on the government’s website on Friday without a formal announcement.
The eight areas are: Bolton, Leicester, Kirklees, Blackburn with Darwen, Burnley, Bedford, North Tyneside and the London Borough of Hounslow.
Shadow health secretary Jonathan Ashworth called on the government to withdraw the guidance, branding the new advice "local lockdowns by stealth, by the back door".
Ashworth said the areas affected felt “abandoned” by Westminster.
Vaccines minister Nadhim Zahawi defended the move, saying Boris Johnson had already told people living in hotspot areas to be “extra cautious”.
A Downing Street spokesman said the new advice was not law, and that the PM wanted to move away from “top-down edicts” as lockdown eases.
Bolton Council leader David Greenhalgh told a press conference that people in the town should “behave sensibly” and that there was no need to “be cancelling holidays”.
It comes as Bolton NHS Foundation Trust said the hospital’s emergency department saw one of its busiest ever days on Monday and that it was braced for continued pressure.
Chief operating officer Andy Ennis said “more people” were turning up requiring treatment from the effects of COVID-19, with 41 currently admitted, including eight in critical care.
“Going into the bank holiday weekend and half term, which is always a busy time for the NHS, we anticipate this pressure continuing,” he said.
“As such we are taking urgent actions to ensure we can continue to manage this demand effectively.”
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