The Labour leadership candidate Andy Burnham has been described as a "grossly unsuitable candidate" by the whistleblower who exposed the Stafford Hospital scandal.

Campaigner Julie Bailey said that the leadership frontrunner, who was health secretary when the full extent of neglect at the NHS Trust emerged, had put himself forward to succeed Ed Miliband, according to The Mail on Sunday.

During 2005-2008, hundreds of patients died at Stafford Hospital amid shortages of nursing staff. In some parts of the hospital, there were only two nurses to care for 40 patients.

The high death rate was revealed by a Healthcare Commission investigation, which began after a campaign led by Bailey.

In the The Mail on Sunday article, Bailey claimed that Burnham was responsible for the crisis at Stafford Hospital. However, Burnham was only appointed to a cabinet position in 2007, within the Treasury. He was appointed

However, Burnham was only appointed to a cabinet position in 2007, within the Treasury. He was appointed secretary of state for health in June 2009, after the scandal had come to public notice and gripped the health services.

Burnham ordered an inquiry into the hospital's failings the following month, despite MPs voting against holding inquiry in May 2009.

Bailey also accused the MP of showing no remorse and said he had not apologised over the scandal.

But Burnham made a statement to parliament in February 2010, stating that "on behalf of the government and the NHS, I repeat that apology again". The previous health secretary, Alan Johnson, had made a public apology in March 2009.

According to Dr Éoin Clarke, founder and director of Labour Left, a left-leaning thinktank, Bailey's claims in the Mail on Sunday amount to a smear campaign.

Earlier in the week, Dr Clarke tweeted that "the Murdoch Press" was starting a campaign aimed at discrediting Burnham, which would include accusations related to the Mid-Staffs scandal.

Cure the NHS' origins

Julie Bailey became a key figure in the Stafford Hospital scandal after her mother Bella Bailey, 86, died after being admitted to Stafford Hospital in September 2007 with an enlarged hernia.

She helped to form the organisation Cure the NHS, which successfully campaigned for a public inquiry into the failings at the hospital.

She told The Mail on Sunday: 'While Health Secretary, Andy Burnham presided over a culture of denial and cover-up over NHS care scandals that cost lives in failing hospitals across the country.

"From ignoring repeated warnings about high hospital death rates, to dodging calls for a public inquiry, Andy Burnham put politics before patients every time.

"Worse still, several experts have independently testified that under his leadership there was political pressure to present good news rather than expose poor care.

"We believe him to be a grossly unsuitable candidate. It would be a disaster for patients if he was ever to become Health Secretary again, let alone assume any higher public office."

A spokesperson for the shadow health secretary rejected the claims, according to paper, stating that Burnham had ordered inquiries into the failings within the Mid Staffordshire NHS trust against civil service advice at the time.

A final report was published on 6 February 2013. It was highly critical and made around 290 recommendations.

The UK's regulator of nurses and midwives struck off a number of a number of nurses deemed to have breached protocol as a result of the inquiry.