"Clusters" of coronavirus cases are breaking out in care homes on the outskirts of London, the city's Public Health England director has revealed.
Tens of thousands of care home residents have died since the virus pandemic began, with recent analysis showing that more than 400 were dying with Covid-19 every day at the height of the crisis.
Speaking to the Evening Standard, Professor Kevin Fenton, the London director of PHE, said some coronavirus clusters were again spreading in care homes.
He said: "For some boroughs where you have high numbers of care homes, especially some of the outer London boroughs, you will tend to see clusters of cases occurring in those care homes."
Prof Fenton added that with more than 100,000 tests a day being allocated for care homes nationwide, it was possible to "get back on track with asymptomatic testing" (see the graphic below for details of how the UK's testing regime breaks down).
Professor Martin Green, the chief executive of Care England, told The Telegraph: "The rise in infection rates is very worrying, particularly for care services – because people who use care services are at the highest risk of contracting the virus."
The comments came as a care home manager described the coronavirus testing system as "a complete farce", with infected staff waiting the length of the mandatory isolation period before receiving their results.
Anita Astle, the managing director at the Wren Hall Nursing Home in Nottingham, currently looks after 54 residents. During the peak of the pandemic, 21 residents died.
She said she ensured that all 142 of her staff were tested for coronavirus on September 4, but they only received the results on September 11 and discovered that four had tested positive.
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"The whole system is a complete farce," she said. "If you're asymptomatic, you have to isolate for 10 days, so by the time those four members of staff received their results they only had to isolate for two days.
"Because getting the results took so long, we could have potentially had 142 Covid-positive staff and 54 Covid-positive residents, so either the tests are farcical or we could argue that they are reliable and the fact that the staff were wearing PPE appropriately meant that it did not spread."
Ms Astle, also a board member at Skills for Care, the strategic body for workforce development in adult social care in England, added: "We need testing at the point of service. Our main concern is the inadequacy of the testing. We do have access, but the results are just coming through far too late."
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A Department of Health and social care spokesman said: "From the start of the pandemic, we have been doing everything we can to ensure care home residents and staff are protected, including testing all residents.
"We are providing tests at an unprecedented scale – 200,000 a day on average over the last week – but there has been significant demand.
"We are expanding capacity rapidly as well as bringing in new technology to process tests faster, and will continue to work around the clock process results as soon as possible."
It comes as new figures revealed that admissions to hospital in England because of coronavirus have risen to their highest levels since July.
The latest Government data reveals that 153 people with Covid-19 were admitted to hospital on Sunday, the highest number since 201 on July 1. There were also 101 coronavirus patients in mechanical ventilation beds in England on Tuesday, the first time that figure has been above 100 since July 23.
It brings the total number of people admitted to hospital with coronavirus in England to 115,097. The north-west has the highest number of admissions, while the east of England has the lowest.