The government was yesterday accused by a powerful committee of MPs of failing to tackle the crisis in hospital-acquired infections, of which the "superbug" MRSA is just a small part.

The public accounts committee, which monitors government spending, said little had been done since its investigation four years ago.

"It is astonishing that poor ward cleanliness, lax hand-washing practices, a shortage of isolation facilities and high bed occupancy rates are still plaguing NHS hospitals," the chairman, Edward Leigh, said.

MRSA rates were still among the worst in Europe, but the bug accounted for only 6% of hospital-acquired infection. The true scale of the problem was still not clear, because "little has been done to dispel the fog of ignorance," he said.

The much-quoted figure of 5,000 deaths a year from infections picked up in hospitals was not only "rough and ready" but it dated from American studies in the 1980s. There was still no mandatory reporting scheme for all hospital-acquired infections, as the committee had recommended, and MRSA infection is included on a death certificate only if the doctor thinks fit.

The criticism came as the Department of Health revealed what might otherwise have been seen as the good news that the numbers of MRSA infections have dropped for a second six-monthly period to give an overall reduction of 6.1% in the year to March.

The health minister Jane Kennedy said: "The figures are encouraging, but they do highlight those trusts that need to focus even more and perhaps haven't got the message," she said. "Cultural changes need to take place at every level."

The Department of Health said that each month strategic health authorities would look at the performance on infections of the six worst specialist trusts and the 11 worst general acute trusts. It added that they had all put in place hand hygiene measures, but they might not have taken effect by the time the figures were compiled.

Brian Duerden, inspector of microbiology at the Department of Health, said that the general international professional view was that 30% of hospital-acquired infections should be preventable. The government has said it wants to cut MRSA infections by 50%.

MRSA is a strain of a very common bacterium called staphylococcus aureus which causes deep abscesses, blood infections and infected wounds. It has become resistant to methicillin, the antibiotic most used against it.

It is mandatory for hospital trusts to report MRSA infections - but only those that get into the bloodstream and are most dangerous. Other bacterial infections, such as Clostridium difficile, which caused 12 deaths at Stoke Mandeville hospital, now also have to be reported to the Health Protection Agency, but reportable infections still amount only to about 20% of the total.

Yesterday it emerged that a second hospital, the Royal Devon and Exeter, was struggling with an outbreak of C difficile.

The committee pointed out that there are at least 300,000 hospital-acquired infections a year, which cost the NHS £1bn each year. It said that progress in implementing the recommendations of its last report had been patchy.

Despite the criticism, Ms Kennedy said the government welcomed "this helpful report from the PAC".

Best performers (reduction in reports 2004/5)

-62 Guy's and St Thomas'

-44 Hammersmith Hospitals

-43 King's College Hospitals

-40 University College, London

-37 Heart of England (Birmingham Heartlands)

-33 Oxford Radcliffe

-31 United Bristol Healthcare

-30 St George's Healthcare

-30 Epsom and St Helier

-25 University Hospitals of Leicester

Worst performers (increase in reports 2004/5)

+31 Bradford Teaching Hospitals

+29 University Hospital Birmingham

+28 Royal Wolverhampton

+24 Kingston Hospital

+22 Aintree Hospitals

+22 Brighton and Sussex University Hospitals

+21 Essex Rivers Healthcare

+21 QE Hospital King's Lynn

+20 James Paget Healthcare

+18 Lewisham Hospital

+18 Lancashire Teaching Hospitals