The problem annually affects 100,000 people and costs the National Health Service �1bn, says the National Audit Office.

When people's lives are at stake this kind of lottery should not be allowed to continue

David Davis MP

It is thought deadly infections are often spread by hygiene rules being broken, like doctors not washing their hands in between treating patients.

The NAO makes a series of recommendations aimed at tightening procedures and increasing investment in infection control, saying that there is "scope to do a lot more".

At any one time, 9% of patients in NHS hospitals are suffering from an infection acquired while on wards or in surgery.

Urinary tract infections are particularly common, but surgical wounds, skin and the bloodstream can all be infected with potentially deadly bacteria.

In extreme cases, antibiotic-resistant superbugs like MRSA - methicillin-resistant staphylococcus aureus - can spread through hospitals.

Control programmes

But the NAO report found that one fifth of NHS trusts do not have an infection control programme and only 40% have a designated budget.

How infections are caught in hospital

From bacteria passed from staff, including doctors who have not washed their hands From equipment such as catheters From bacteria such as Staphylococcus aureus passed through surgical wounds and intravenous lines Infectious diseases such as influenza, gastro-enteritis or Legionnaires Disease spread from patient to patient

Sir John Bourn, head of the NAO, called on the Department of Health to update its guidelines on infection control and said all hospitals should take part in the Nosocomial - hospital acquired - Infection National Surveillance Scheme.

He urged hospital trusts to involve senior clinicians and management in infection control.

He said: "Hospital acquired infections are a huge problem for the health service. They prolong patients' stays in hospital and, in the worst cases, cause permanent disability and even death.

This is all well and good but we need strategic investment to get away from the current levels of bed occupancy

Stephen Thornton, NHS Confederation

"By implementing the NAO recommendations the NHS could make real improvements in the quality of care for patients and could free up significant additional resources for patient care."

One of the report's authors, Dr James Robertson said senior management needed to get more closely involved in infection control programmes.

"Fifty percent of hospital Chief Executives are not getting reports on the amount of infection in their hospitals and a similar number don't know how much their hospital is spending on it," he told BBC Radio 4's Today programme.

The NAO estimates that as well as saving lives, �150m a year could be saved by the NHS.

David Davis MP, chairman of the Committee of Public Accounts, said: "When people's lives are at stake this kind of lottery should not be allowed to continue.

"There is no excuse for poor hand-washing, where doctors seem to be the worst culprits. More generally, at too many hospitals the problem is simply not taken seriously enough."

Paul Flynn, MP, said: "We know these deaths are avoidable. The answer is to have wards which are kept cleaner."

Hospital Acquired Infections (HAIs)

The most common HAIs are urinary tract infections and infections at the site of surgical wounds. One of the most severe, albeit rare, HAIs is a bloodstream infection caused by an antibiotic-resistant strain of the bacterium Staphylococcus aureus known as MRSA. A US study found that patients infected with MRSA had to stay in hospital three times longer than those who were not infected.

But the NHS Confederation said savings would not be easy to achieve.

Chief executive Stephen Thornton said: "There are things we can do about it - basic hygiene is important - but we must invest in infection control doctors and nurses across the country."

And Sir Alan Langlands, chief executive of the NHS, told BBC Radio 4's Today programme: "These figures need to be seen in perspective. The figures on deaths are based on a very crude comparison with US figures from the 1970s.

"For the first time we have a national strategy for dealing with hospital acquired infections, better information systems and standards for dissemination of good practice."

He refused to set a target for reducing the numbers of deaths and added that he did not think more people were dying from infections contracted in hospitals than 10 years ago.