There is a grand tradition of rewarding failure in the City. Often news that the latest company with soaring losses has given its chief executive the boot – but only after stuffing a couple of hundred thousand down his trousers to soften the blow – takes the mind of the average-waged nine-to-fiver off their mortgage worries.

Things are a little different where the public's cash is on the line. The Secretary of State for Health, Alan Johnson, acted quickly last week when Rose Gibb, the chief executive of Maidstone and Tunbridge Wells NHS Trust quit after four years in the post.

Police are deciding whether to prosecute the trust in Kent after it emerged that up to 90 patients may have died as a result of its poor handling of the infection Clostridium difficile, a bug that infects the gut and affects mainly the elderly.

The Healthcare Commission described the deaths over a two-and-a-half-year period as a "tragedy". It launched an investigation after receiving complaints about cleanliness in the hospital, and discovered that nurses were too busy to wash their hands and left patients to lie in their own excrement.

Among those who died was Ranjit Gosal, 71, who was admitted to the hospital for a routine operation this year. The operation went well, but then the trouble started.

"It was a dirty ward, and the beds were very close together. The woman in the next bed had really bad diarrhoea – which I now know was in all likelihood linked to C difficile infection," her son, John, told the BBC. His mother contracted the disease and died.

The hospital chief executive, Ms Gibb, left the trust last Friday, days before the report came out. The trust has refused to reveal details of severance pay, though some sources suggest it could be as high as £250,000. She was earning £150,000 a year, plus a £12,500 pension and £5,000 in other benefits.

Mr Johnson called the deaths "scandalous", and ordered the trust to withhold any severance pay pending legal advice.