A group representing care home providers in the UK has estimated that about 4,000 residents have died during the coronavirus pandemic and has called on the government to build a “ring of steel” to safeguard “the most vulnerable among us”.

The National Care Forum said that once the deaths of residents who had been moved to hospital were factored in, the true toll was likely to be more than 7,300.

Data collected by the NCF, which represents not-for-profit adult social care providers, suggests 4,040 people may have died from Covid-19 in residential and nursing homes up to 13 April but are yet to be included in official figures.

The figures will further fuel concerns that the recorded death toll does not give a true picture of the number of fatalities, and according to the NCF they highlight “significant flaws in the current national reporting”.

The NCF also found a doubling of deaths related to Covid-19 (2,500) in residential and nursing homes in the space of one week. Only 217 such care-home deaths had been officially recorded in England and Wales up to 3 April.

The NCF collected data from care homes that look after more than 30,000 people in total. That number represents almost 7.5% of all people living in such accommodation in the UK.

It said that in the week from 7-13 April there were 299 deaths linked to the coronavirus, three times more than in the previous week and double the number in the whole of the previous month.

Vic Rayner, the NCF’s executive director, said: “By highlighting the scale of the tragedy, we are giving the government an opportunity to respond with equal effort. It must act immediately and build a ‘ring of steel’ around care homes. They need the right PPE [personal protective equipment], medical monitoring devices, rapid and comprehensive testing, proper funding and intensive research to safeguard the people they care for.”

She added: “So long as groups such as residents in care services are omitted from the real-time national reporting on the impact of the coronavirus pandemic, the government will surely be unable to properly plan for how to protect its people or exit this crisis.

“Our current national debate on how to mitigate and exit this crisis is virtually entirely centred on the management of the peak within hospitals. We are overlooking how this crisis is playing out in other settings, which are there to protect those who are most vulnerable to the impact of the virus. If we truly believe that every life has value, there can be no meaningful discussions about exit strategies without considering these individuals.”

The official figure of 217 has been questioned as two of the UK’s largest care home providers, HC-One and MHA, said they collectively knew of 442 coronavirus-related deaths.

Separately, analysis from Care England suggests there have been 7,500 more deaths in care home from all causes in the past fortnight than would be expected at this time of year.

The daily number of UK-wide coronavirus deaths, announced each day by the government, only includes people who died in hospital. Virus-related deaths in care homes and elsewhere are measured separately, and figures for England and Wales are announced every Tuesday by the Office for National Statistics.

There is a two-week delay on collecting the data from thousands of care homes involved because it is derived from death certificates issued by doctors.

The Care Quality Commission, England’s health and social care regulator, said it was working to provide more detailed information about how the pandemicwas affecting care homes.

The Department of Health and Social Care said: “Every death from this virus is a tragedy and that is why we are working around the clock to give the social care sector the equipment and support they need to tackle this global pandemic.”

It said it was focusing on providing tests for care workers and their families and ensuring that workers get access to any protective equipment that they require.