More than half of care homes have had a confirmed case of Covid-19, a Government survey has shown.
The Office for National Statistics (ONS) also released separate data on Friday showing that 20,000 care home residents in England and Wales have died with coronavirus, with the majority of those people dying in their care home.
The figures have prompted clinical negligence lawyers to warn that "critical shortcomings" have led to "many unnecessary deaths".
A survey looking at infections in more than 9,000 care homes in England between May 26 and June 20 estimates that more than half – 56 per cent – have had at least one confirmed case of coronavirus.
Some 5,126 care homes responded to the Vivaldi study, which looked at coronavirus infections in 9,081 care homes providing care for dementia patients and the elderly in England, and estimates were produced by weighting the actual responses to take account of the care homes that did not respond.
Of these, 20 per cent of residents and seven per cent of staff are estimated to have tested positive for Covid-19 since the start of the pandemic, as reported by care home managers.
The results differ from the latest Public Health England (PHE) statistics, which say that 43 per cent of care homes in England have had an outbreak, defined as two or more suspected or confirmed cases.
Meanwhile, separate ONS data showed that death certificates for 19,394 residents between March 2 and June 12 mentioned "novel coronavirus".
Covid-19 accounted for 29 per cent of the deaths of care home residents over this period, and one fifth of all deaths of care home residents this year.
The latest data includes all care home residents who died with coronavirus, either at their care home or in hospital. This pushes the overall care home resident death figure 32 per cent higher than the 14,658 deaths in care homes reported by the ONS on Tuesday.
Three-quarters (74.9 per cent) of residents died in their care home, while a quarter (24.8 per cent) died in hospital, the figures show. Some 65 residents, representing 0.3 per cent of the total, died in a separate location such as a private home or hospice.
Responding to the latest data, Victoria Beel, a clinical negligence lawyer at Slater and Gordon, said: "The Government's response to tackling Covid-19 in care homes has been slow and involved a number of failings.
"Initially, plans to control the virus overlooked these homes, despite the 400,000 residents being the UK's most vulnerable.
"These decisions and critical shortcomings led to many unnecessary deaths. A public inquiry is the best way forward to honour the lives lost, provide answers to grieving families and prevent this from happening again."