Isolating intensive-care patients infected with MRSA does not reduce cross-infection

Results of a UK study published online suggest that the widely practised approach of isolating intensive-care patients infected with MRSA does not reduce cross-infection. Authors of the study caution that this finding should not be extended to general hospital wards, and needs further confirmation from larger studies.

Hospital-acquired infections cost the UK National Health Service around £1 billion a year. A fifth of these infections are caused by meticillin-resistant Staphylococcus aureus (MRSA), especially within intensive-care units. Single room or group isolation of patients infected or colonised with MRSA is commonly used to reduce spread, but its benefit over and above other contact precautions is not known.

Peter Wilson, Geoff Bellingan, and colleagues from University College London Hospitals and the Royal Free Hospital, UK, did a prospective 1-year study in the intensive-care units of these two London teaching hospitals. Admission and weekly screens were used to ascertain the incidence of MRSA colonisation. In the middle 6 months, MRSA-positive patients were not moved to a single room or treated as an infected group of patients unless they were at risk of spreading other serious infections. Standard precautions were practised throughout, with hand hygiene encouraged at all times.

Patients’ characteristics, staff hand-washing frequency, and MRSA acquisition rates were similar in the periods when patients were moved and not moved. There were no changes in transmission of any particular strain of MRSA or in infection rate between management phases.

Dr Wilson comments: “Our findings challenge the prevailing view that isolation of intensivecare unit patients who are colonised or infected with MRSA in single rooms or cohorts reduces the transmission of MRSA, over and above the use of standard precautions, in an environment in which it is endemic.”

In an accompanying commentary also published online Friday January 7, Donald A Goldmann (Institute for Healthcare Improvement, Cambridge, Mass, USA) and Charles Huskins (Mayo Clinic, Rochester, USA) highlight hand hygiene and proper use of gloves as the most important interventions for preventing contamination of the hands of health care providers – the main ‘vectors’ for spreading MRSA in hospitals. They note that compliance with hand hygiene in the centres taking part in this study was only 21 %.

Dr Goldmann states: “The public, particularly in the UK, has focused on cleaning up “dirty” hospitals. While order and cleanliness probably are surrogates for overall attention to detail within an organization, housekeeping programs are unlikely to have a substantial impact on MRSA transmission. There are more important steps that can be taken now. Health care institutions simply must expect more reliable performance of essential infection control practices, such as hand hygiene and proper use of gloves.

He concludes: “Most institutions still tolerate “defect” or “failure” rates in hand hygiene of 40% or more—levels that would be considered shocking in any other industry. To achieve even a relatively modest level of reliability (failure rates under 10%), the availability of waterless alcohol-based hand rubs, sinks, gloves, and gowns should be reviewed applying ergonomics and human factors principles.”