MRSA infections are just the beginning

Wednesday, July 30, 2008

Dr Stephen Barrett, Honorary Secretary of the Association of Medical Microbiologists, explains why statistics may not show the full extent of HAI infection rates.

Although the first UK national survey of healthcare associated infection (HAI) was in 1980,¹ infection control had a slow start. The mid-1980s then saw the deaths of 19 patients from hospital-acquired salmonella in the Stanley Royd Hospital, and 22 from hospital-acquired Legionnaires disease in Staffordshire, which tragically emphasised the roles of cross-transmission and of the environment in HAIs. The resulting public enquiries and subsequent Department of Health guidance created the 'Infection Control Doctor' and raised the importance of infection control, including direct access to the hospital's chief executive.

These two dramatic outbreaks were fortunately exceptional, but they did set the ball rolling. Thereafter the impetus was partly sustained by public concerns over the predominantly hospital-based MRSA – for which specific control guidelines first appeared in 1986² – and more solidly by the long-term wider focus of infection control workers on HAIs overall. From the late 1980s onwards, and especially in the last few years, recognition of the importance of infection control in the healthcare environment has grown to make it now a major issue in the delivery of healthcare in the UK. We have now had a vast range of initiatives, mostly emanating from the Department of Health, trying to tackle HAIs in a variety of ways. Whilst in essence these do not advocate any new-found principles – we still have the traditional methods of good hygienic practice, isolation nursing and screening when necessary – the force of the message of infection control, and the requirement to take it seriously, is now promoted much more vigorously.

In this context the 2003 publication Winning Ways³ laid out the areas that should be addressed in order to reduce HAIs, including surveillance, environmental hygiene, antimicrobial resistance and infection risks related to invasive devices. These themes were further developed in specific documents such as the Matron's Charter⁴ focusing on overall hospital cleanliness, and the Saving Lives⁵ campaign that promoted best practice in situations where infection risks were especially high. There have also been external initiatives such as the cleanyourhands⁶ campaign by the National Patient Safety Agency. In addition to the creation of all these frameworks within which infection control is to be managed, measures of compliance are used such as those undertaken by Patient Environment Action Teams, and the counting of cases of specific infectious agents, initially MRSA and more recently Clostridium difficile.

Having complained in decades past about a lack of interest and support, infection control teams now carry out their daily tasks with arguably more initiatives and compliance requirements than they can comfortably cope with. At a day to day level the practice of infection control has to go on. Infection control workers must still discuss the isolation of infected patients in hospitals permanently short of isolation facilities, and the closure of wards with outbreaks of diarrhoea. They must advise on investigating outbreaks of infection and on decontaminating MRSA-colonised patients. They must ensure that policies for invasive procedures minimise infection risks. They have to check that new equipment does not entail unexpected infection risks, and advise on antiseptics, disinfectants, and cleaning regimens for the patient environment. What particularly hampers them, though, is lack of information. Tracking infection rates, as opposed to counting numbers of positive microbiology reports, is beyond the capacity of infection control teams. No-one has the resources to get an infection control nurse to check each patient every day and decide whether the patient has an HAI. Only in exceptional circumstances and in response to some specific problem, might this be attempted. Improving the poor microbiology IT systems serving most infection control teams goes only a little way towards addressing this. However carefully one analyses laboratory data, they are entirely dependent on a clinician's deciding to send a sample to the lab, and this can be in no way substitute for prospective observation of the patients.

Whilst the considerable resources needed to undertake real-time clinical surveillance of infection have not been forthcoming, infection control teams are now much better supported by the Department of Health and other agencies in dealing with clinicians and managers. The highly visible cleanyourhands campaign and the incorporation of the Saving Lives 'care bundles' into clinical practice, have made it impossible to ignore the message of infection control. Often these initiatives – for example the recent requirement to dispense with ties and to work 'bare below the elbows' – are open to challenge on the basis of a lack of evidence. Even the washing of hands is difficult to support with clear evidence, though a moment's thought will make it obvious that no clinical trial of the value of hand washing could possibly be undertaken. The real point though is to instil a culture of awareness of the risk of infection and of overall careful hygienic practice. Initiatives that may be considered more contentious are, for example, the move towards universal screening for MRSA of all patients admitted to hospital. The resource implications here are considerable and some recent publications⁷ have suggested that the more costly rapid screening methods being advocated have no impact on MRSA anyway.

It must however be recognised that MRSA has a unique place in driving infection control.⁸ It was highlighted as a matter of concern in Winning Ways that Britain had an excessive proportion of MRSA, even though overall HAI rates were similar to the rest of the world's. Similarly, the Clean, Safe Care campaign is subtitled: 'reducing MRSA and other healthcare associated infections',⁹ further emphasising the special role of MRSA.

Whilst the particular importance accorded to MRSA can be questioned, it is visibly a matter of major concern to the mass media and is a readily measurable index of cross infection. Because it is easily identified by laboratories; computer records allow rates to be compared between hospitals and time periods. The setting of reduction targets for MRSA bloodstream infections was therefore the simplest means of giving hospitals measurable infection control performance targets. Against the criticism that MRSA bloodstream infections account for less than 2% of hospital acquired infections,¹⁰ it has been argued that their reduction implies that of other infections, although the evidence for this is uncertain.

Although MRSA has grabbed the media's attention for many years, awareness of other HAIs is growing. The last couple of years has seen much attention given to Clostridium difficile diarrhoea, an infection that again emphasises environmental contamination as a source of infection. The much publicised outbreaks at Stoke Mandeville and Maidstone have resulted in further initiatives around environmental cleanliness and antibiotics, which are currently in preparation. The next microorganisms to cause concern may well be the extended spectrum beta-lactamase (ESBL) producing Gram-negative bacteria, which are now widespread in the community as well as in hospitals. Counting these should again be within the capabilities of laboratory computer systems, but the goal of analysing infections, and not just laboratory reports, still remains to be reached.

1 Meers P D, Ayliffe G A J, Emmerson M E et al. 'Report on the national survey of infection in hospitals', 1980. J Hosp Infect 1981; 2 Suppl.: 1-51
2 Report of a combined working party of the Hospital Infection Society and British Society for Antimicrobial Chemotherapy. 'Guidelines for the control of epidemic methicillin-resistant Staphylococcus aureus'. J Hosp Infect 1986; 7: 193-201
3 Department of Health (2003) 'Winning Ways. Working together to reduce Healthcare Associated Infection in England'. London DH
4 Department of Health (2004) 'A Matron's Charter: An Action Plan for Cleaner Hospitals' London DH
5 Department of Health (2005) 'Saving Lives: reducing infection, delivering clean safe care'. London DH
6 cleanyourhands© National Patient Safety Agency 2004
7 Harbarth S, Fankhauser C, Schrenzel J et al. 'Universal screening for methicillin-resistant Staphylococcus aureus at hospital admission and nosocomial infection in surgical patients'. JAMA 2008; 299:1149-57
8 Department of Health (2007) 'MRSA Equality Impact Assessment'. London DH
9 Department of Health (2006) 'Clean Safe Care; reducing MRSA and other healthcare associated infections'. London DH
10 The Hospital Infection Society. 'The Third Prevalence Survey of HCAIs in Acute Hospitals – Results for England'. J Hosp Infect 2008; in press