Health care acquired infections are costing the NHS £1 billion a year and leading to 5,000 deaths according to a critical report by the House of Lords Select Committee on Science and Technology.

The report found that measures to limit the spread of infections within hospitals were inadequate. Handwashing, for example, is a key intervention to reduce the spread of infection and yet it is known that many health care workers do not wash their hands when moving between patients. The report recommends more research to inform those who organise services how best to design wards and run services so as to minimise the barriers to handwashing. This could be as simple as providing more sinks and washing equipment for doctors and nurses.

Outbreaks of infection such as the Norwalk virus (causing diarrhoea and vomiting) can lead to wards being shut down. This significantly increases pres-sure on beds and can lead to a reduction in the numbers of available staff.

Clinical microbiologists and infection control nurses play an important role in implementing control measures in hospitals but the report found that these two groups were accountable to different people within the hospital - a situation that often resulted in confusion.

This problem of confused lines of responsibility was in evidence throughout infection control procedures, the report found. One example of this concerned an individual who developed psittacosis, which is a potentially fatal pneumonia usually contracted from birds. The patient had recently bought a parrot from a large bird show. The community infection control team wanted to ascertain whether the patient had caught the infection from this parrot in order to know whether other people at the show might be infected. However nobody could decide whether it was DEFRA, the local authority or the consultant in communicable disease control who was responsible for taking a sample from the parrot. Eventually an environmental health officer from the local authority had to be persuaded to take droppings from the parrot's cage, although he protested it was not his job.

The select committee report claims that improvements in infection services are essential to ensure that England is better prepared to control and prevent epidemics. It recommends that the government establish a limited number of "infection centres" around the country to provide identified centres of infection expertise and rapid access to infection experts.

The chairman of the committee which produced the report, Lord Soulsby, said: "The government must act now to improve services that protect us from infection. We can never conquer infection, but we must be better equipped to fight it. Arrangements for formal collaboration between those involved in the fight against infection are poor and lines of accountability unclear. The government should address this as a matter of urgency."

The report comes at a time when standards of cleanliness and food in NHS hospitals have improved significantly, according to new figures from the department of health. The results show that 192 hospitals were awarded the top "green" rating for cleanliness and food on the government's "traffic light" system, double the number that received the rating last year.

However the claims were immediately dismissed as untrustworthy by opposition parties who said that the department of health ratings, which were introduced two years ago, bore no resemblance to the reality of patients' experiences.

As with last year no hospitals received the red rating. The number of hospitals given a green rating for cleanliness has risen from 60 per cent to 78 per cent. The government has invested £68 million in the clean hospitals programme. Health minister Lord Warner said: "Keeping hospitals clean and tidy is not a one-off exercise and the importance of the Clean Hospitals campaign has been maintained during 2002 to make sure things continue to improve."

However Liam Fox, the shadow health secretary, said: "Everybody knows that you cannot trust the department of health's statistics assessing its own performance when they are created by the department itself. The ratings bear no relation to the quality of care that patients receive. The picture painted by the department of health's recent survey of 95,000 patients revealed that 11 per cent of patients said bathrooms and toilets were dirty and seven percent said the same about wards."

The Liberal Democrats revealed earlier this year that out of the 40 hospitals with the most MRSA or "superbug" cases none was classed as a "dirty" hospital under the ratings system. Liberal Democrat health spokesman, Evan Harris, said: "The clean hospital programme should be prosecuted under the Trade Descriptions Act. It is nothing of the sort. It covers different standards of which only one is about cleanliness and none is about the control of infection."