Care homes in England operated by profitable chains have been branded unsafe by inspectors, who found serious failures in efforts to control the spread of coronavirus in its latest wave.

In the last month 40% of care homes inspected by the Care Quality Commission in England were judged to be inadequate or in need of improvement. Several handling fatal coronavirus outbreaks were revealed to have broken laws meant to keep residents safe.

Some of the worst failings uncovered in reports filed in the last month include CCTV showing PPE being used wrongly on 63 occasions in one home, infected residents mixing in communal areas with Covid-free residents, chronic staff shortages, and a care home manager continuing to work after showing Covid symptoms.

The spate of problems relates to a small minority of care homes but coincides with a tripling of fatalities linked to the virus among care residents in England and Wales.

In the week ending 22 January, 2,364 care residents died with Covid-19 on their death certificate, the highest level since last May, according to the Office for National Statistics.

At Curtis Weston House, a home for 27 people in Wigston, Leicestershire, which is part of a chain that made £2.2m in annual post-tax profits, inspectors found “no deep cleaning of bedrooms of Covid-19 positive people”, ineffective alcohol-free hand sanitiser in use, and staff not always having ready access to PPE.

Another home in the same chain, Huntington Court, in Loughborough, was also branded inadequate. Inspectors found that infection prevention and control procedures were not in line with government guidance, which meant “people were put at increased risk of infection”. The firm, Leicestershire County Care Limited, did not respond to request for comment.

Inspectors said Talbot House, in Rugely, Staffordshire, owned by a company with nearly £800,000 profit on its balance sheet, “had not kept people safe during the pandemic, and a high number of people and staff had been adversely affected”. They said an outbreak caused a small number of fatalities and was linked to the admission of two people to the home. The provider had not been using PPE properly, the inspectors said.

The home’s director, Om Gupta, said there was “no evidence of that” and said there was no lack of financing for the home. “It was just unfortunate my manager and deputy manager went off sick with Covid,” he said.

Scrutiny of CCTV footage from the Ashton care home in Hinckley uncovered dozens of occasions when staff did not wear the right PPE or were seen working with face masks around their necks.

“On three occasions we observed staff administering medicines directly into people’s mouths without wearing gloves, aprons, or [without] washing hands,” the inspectors said.

They found that at a time when one person had returned from hospital – a common route for virus spread – there was no infection control prevention plan in place at the care home. Where people were isolating in their rooms, doors were left open, and inspectors observed a staff member walk into the room of a person who was isolating and provide support without wearing any PPE.

CQC said the Ashton home was not safe and had breached the Health and Social Care Act. The home’s operator, Care Concern Group, declined to comment.

The shadow social care minister, Liz Kendall, said: “These reports will be desperately worrying for families with loved ones living in care homes. It is unacceptable that some care companies are failing to put even basic infection control measures in place and even turning down offers of training and other support.

“Ministers must look at these reports as a matter of urgency and spell out what action they and the CQC will take against providers who repeatedly fail to show the necessary leadership.”

Analysis of the latest inspection reports reveal repeated concern about shortages of staff and leadership in some care homes – factors exacerbated by high levels of absence arising from routine Covid testing that required workers to self-isolate.

At the Firs home in Budleigh Salterton, Devon, which had a large coronavirus outbreak in November and December 2020 that led to some fatalities, inspectors discovered a lack of mask-wearing and social distancing.

Liana Birkett, whose family run the home, said: “The day of the Covid inspection our manager was off sick with the virus and we didn’t have all our own staff in due to many of them being struck down by the virus or having to self isolate.”

She accepted mistakes had been made on the day of inspection, but said the issues had since been fixed.

Staff problems at the Woodheyes care home in Leicestershire, which had a Covid outbreak, meant residents who needed oxygen were not supported safely.

“Staff did not have all the skills and knowledge needed to provide safe care,” inspectors concluded. “We observed people with Covid-19 in communal areas, mixing with people that did not have Covid-19 … we observed staff entering and exiting bedrooms [of infected residents] without changing their PPE … The registered manager had declined Covid-19 training offered by partner agencies.”

The home’s manager did not respond to a request for comment.

At Swan House, a care home in Buckinghamshire where two people died in a Covid outbreak in April, staff meeting records indicated that the registered manager continued to work on site after developing potential symptoms of Covid-19. Staff worked in different units of the home without consideration of the risk of cross infection, and a lack of ventilation meant use of fans, which increased the risk of spreading the infection.

The operator, Ambient Support, a £38m-a-year-turnover charity operating care homes across several English counties, said: “[We] fully accept the findings of the report and [are] delivering an action plan to address the issues raised.”

Kate Terroni, CQC’s chief inspector of adult social care, said: “Where there has been poor care or inadequate infection control procedures, we have taken immediate action. However, in most cases care providers that we have inspected have shown they are responding well to the challenges of infection prevention control during the pandemic and doing everything they can to keep people safe.”

• This article was amended on 4 February 2021 to include the location of Swan House, and to clarify that two people died there in April, rather than the deaths being “recent” as an earlier version said. It was further amended on 5 February 2021 to clarify that the Woodheyes care home is in Leicestershire, not the Leicester city council area.