Evaluation of the national Cleanyourhands campaign to reduce Staphylococcus aureus bacteraemia and Clostridium difficile infection in hospitals in England and Wales by improved hand hygiene: four year, prospective, ecological, interrupted time series studyBMJ 2012; 344 doi: https://doi.org/10.1136/bmj.e3005 (Published 03 May 2012) Cite this as: BMJ 2012;344:e3005
All rapid responses
There is no doubt that the Cleanyourhands campaign has raised the profile of hand hygiene, with those responsible for infection control charged with implementation at every level.1 But to infer that the programme has been the sole driver for reducing the rates of some hospital-acquired infections (HAIs) is an assumption too far. Clinically relevant hand hygiene is not necessarily measured by consumption of soap or gel products; and HAI rates should not be linked to ‘splosh-and-go’ when there are so many other factors affecting microbial transmission. Sophisticated modelling of selected markers does not provide sufficient reassurance that hand hygiene, however performed, is our predominant defence against hospital infection.1
Given that hospitals must report staphylococcal bacteraemias, it is obvious why this marker was chosen for monitoring, but it does not include all clinical acquisitions.2 Methicillin-resistant Staphylococcus aureus (MRSA) in blood only reflects the tip of the proverbial iceberg.3, 4 There are many other types of clinical specimens.5 All hospital acquisitions of MRSA are significant, not just those ultimately ending up in the bloodstream. Indeed, the campaign had no effect on methicillin-susceptible S. aureus (MSSA) bacteraemias; presumably because MSSA does not attract the same level of infection control attention as its multi-resistant counterpart.6 Why blame the community? There is no easy explanation for increasing numbers of patients admitted with MSSA bacteraemia. Patients are not generally screened for MSSA, however, whereas increasing interest in MRSA screening occurred during the campaign period.7-11 It was suggested as national policy in 2007 but there are no available data for comparable national level analyses.11 We know that patient screening prevents subsequent infection.12 Could screening not have affected MRSA rates, piecemeal as it may have been, leaving MSSA to flourish? As soon as MRSA carriage is identified, a barrage of control practices is unleashed, including isolation; topical decontamination; antimicrobial review; contact screening; catheter care; and follow-up, amongst others.13 Managerial focus on imposed MRSA targets means that superficial MRSA, smothered by mupirocin, fails to progress to bacteraemia.
Similarly, C.difficile responds to additional infection control measures, including environmental decontamination and antibiotic stewardship. The latter is well established in the control of C.difficile.14 In one (Scottish) hospital, ceftriaxone consumption fell from 46 to 2 DDDs/1000 patient-occupied bed-days over a two year period, resulting in a 77% reduction in hospital-acquired C.difficile-associated disease (correlation 0.83; p> 0.005).15 Overt monitoring of hand hygiene over the same period reported the usual compliance rates of 90% or so, but the covert option revealed a real life rate of just 25%, perhaps because Cleanyourhands didn’t cross the border.16
Aside from the role of antibiotics, the politicised compulsory ‘deep clean’ of hospitals in 2007-8 was unmentioned. 17 This served to focus on the much documented state of hospital cleanliness and doubtless initiated managerial attention on domestic services. Improved cleaning is known to be beneficial for a multitude of hospital pathogens, including MRSA and C.difficile.18 Contact surface area of a ward is, after all, rather more than that of the hands of its staff. Furthermore, admission of a patient into a bed previously occupied by an infected patient significantly increases their chance of acquiring the same pathogen, regardless of compliance with hand hygiene.19 Newly cleaned hands touching contaminated environmental sites consistently undermine hand hygiene success.18, 20
It only remains to say that whilst UK MRSA bacteraemia and C. difficile rates have dipped, no such trend has been observed for multi-drug resistant coliforms. The increasing rate of gel consumption mirrors the inexorable increase in resistant E. coli bacteraemias.1,21 Could the two be linked? Indeed, no amount of gel would do much to rebut the hugely troublesome and increasingly frequent outbreaks of norovirus.22 The authors should not allow well-meaning zeal to cloud their analyses. Reductions in MRSA and C.difficile rates across the UK are the result of intense and targeted team work on multiple fronts.13,17 Not withstanding the contribution from hand hygiene programmes, all those responsible for infection control in hospitals should be thanked for their hard work. They might now ponder the means to retain emphasis on all hygienic activities. Only continued prominence of the importance of ‘clean’ will ultimately provide the defence we need from inevitable super superbugs.23
Stephanie J. Dancer
1. Stone SP, Fuller C, Savage J, Cookson B, Hayward A, Cooper B et al. Evaluation of the national Cleanyourhands campaign to reduce Staphylococcus aureus bacteraemia and Clostridium difficile infection in hospitals in England and Wales by improved hand hygiene: four year, prospective, ecological, interrupted time series study. BMJ 2012; 344: e3005.
2. Department of Health. Mandatory bacteraemia surveillance scheme—MRSA bacteraemia by NHS trust: April 2001-March 2004. www.dh.gov.uk/assetRoot/04/08/58/93/04085893.pdf
3. Harbarth S, Martin Y, Rohner P, Henry N, Auckenthaler R, Pittet D. Effect of delayed infection control measures on a hospital outbreak of methicillin-resistant Staphylococcus aureus. J Hosp Infect 2000; 46: 43-9.
4. Walker S, Peto TEA, O'Connor L, Crook DW, Wyllie D. Are there better methods of monitoring MRSA control than bacteraemia surveillance? An observational database study. PLoS ONE 2008; 3(6): e2378.
5. Pollard TC, Newman JE, Barlow NJ, Price JD, Willett KM. Deep wound infection after proximal femoral fracture: consequences and costs. J Hosp Infect 2006; 63: 133-9.
6. Millar M, Coast J, Ashcroft R. Are meticillin-resistant Staphylococcus aureus bloodstream infection targets fair to those with other types of healthcare-associated infection or cost-effective? J Hosp Infect 2008; 69: 1-5.
7. Cunningham R, Jenks P, Northwood J, Wallis M, Ferguson S et al. Effect on MRSA transmission of rapid PCR testing of patients admitted to critical care. J Hosp Infect 2007; 65: 24-8.
8. Gopal Rao G, Michalczyk P, Nayeem N, Walker G, Wigmore L. Prevalence and risk factors for meticillin-resistant Staphylococcus aureus in adult emergency admissions – a case for screening all patients? J Hosp Infect 2007; 66: 15-21.
9. Hardy KJ, Szczepura A, Davies R, Bradbury A, Stallard N, Gossain S et al. A study of the efficacy and cost-effectiveness of MRSA screening and monitoring on surgical wards using a new, rapid molecular test. BMC Health Serv Res 2007; 7:160.
10. Guleri A, Kehoe A, Hartley J, Lunt B, Harper N, Palmer R et al. The costs and benefits of hospital MRSA screening. Br J Healthcare Management 2011; 17: 64 – 71.
11. Department of Health. Screening for meticillin-resistant Staphylococcus aureus (MRSA) colonisation. A strategy for NHS trusts: a summary of best practice. London: DoH, 2007.
12. Davis KA, Stewart JJ, Crouch HK, Florez CE, Hospenthal DR. Methicillin-resistant Staphylococcus aureus (MRSA) nares colonization at hospital admission and its effect on subsequent MRSA infection. Clin Infect Dis 2004; 39: 776–782.
13. Dancer SJ. ‘Everything has made the difference’ – a reply to Dr Elston. J Hosp Infect 2010; 75: 136-7.
14. Khan R, Cheesbrough J. Impact of changes in antibiotic policy on Clostridium difficile-associated diarrhoea (CDAD) over a five-year period in a district general hospital. J Hosp Infect 2003; 54: 104-8.
15. Dancer SJ, Kirkpatrick P, Corcoran DS, Christison F, Farmer D, Robertson C. Temporal effects of a restrictive antibiotic policy on hospital-acquired Clostridium difficile, methicillin-resistant Staphylococcus aureus and extended-spectrum ?-lactamase producing coliforms in a district general hospital. Abstract no.096, 20th ECCMID, Vienna, 10-13 April 2010. Available at: http://www.blackwellpublishing.com/eccmid20/abstract.asp?id=83342
16. Smith SJ, Young V, Robertson C, Dancer SJ. Where do hands go? An audit of sequential hand-touch events on a hospital ward. J Hosp Infect 2012; 80: 206-11.
17. Mooney H. Was the deep clean worth it? Nursing Times.net 7th April 2008. At: http://www.nursingtimes.net/was-the-deep-clean-worth-it/1080132.article
18. Dancer SJ. The role of environmental cleaning in the control of hospital-acquired infection. J Hosp Infect 2009; 73: 378-85.
19. Carling PC, Bartley JM. Evaluating hygienic cleaning in healthcare settings: what you do not know can harm your patients. Am J Infect Control 2010; 38: S41-S50.
20. Creamer E, Dorrian S, Dolan A, Sherlock O, Fitzgerald-Hughes D, Thomas T et al. When are the hands of healthcare workers positive for meticillin-resistant Staphylococcus aureus? J Hosp Infect 2010; 75: 107–111.
21. Canton R, Akova M, Carmeli Y, Giske CG, Glupczynski Y, Gniadkowski M et al. Rapid evolution and spread of carbapenemases among Enterobacteriaceae in Europe. Clin Microbiol Infect 2012; 18: 413-31.
22. Health Protection Agency. 2012. Guidelines for the management of Norovirus outbreaks in acute and community health and social care settings. Available at: http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1317131639453
23. Dancer SJ. Infection control ‘undercover’: a patient experience. J Hosp Infect 2012; 80: 189-91.
Competing interests: No competing interests
We note that the results of Stone et al. are consistent with mathematical models of MRSA transmission within hospitals. This can be demonstrated using the framework suggested by Cooper et al (Proc Natl Acad Sci USA 2004; 101: 10223-8). In the model, the transmission within hospital is described by an effective contact rate between susceptible and infectious individuals. Hence improved hygiene conditions correspond to a reduction in the probability that contact between individuals results in transmission and hence a reduction in the contact parameter.
In the figure below, we have plotted the expected prevalence (number of bacteraemia cases per 10,000 bed days) as a function of changes in the contact parameter, for the long-term equilibrium of the system. The model predicts a notable sensitivity response in MRSA rates to small reductions in contact rate, suggesting that relatively small reductions in transmission, via programmes such as hand hygiene programmes, can impact considerably on overall bacteraemia rates.
The delay in the efficacy of the programme described by Stone et al is not readily explained by the long term behaviour of the model alone, as the relationship between transmission reduction and equilibrium prevalence is approximately linear (for those parameters of relevance here), and as noted in the paper, there may have been significantly increased compliance with hygiene measures in the last year of the study only. However, the delay could also possibly be due to transition time from one endemic equilibrium to another. This time depends on the contact parameter, and the state of the system at the onset of changes in hygiene measures.
Simulations of the model show that this is dependent on the initial conditions (i.e. how close to an equilibrium the system was in prior to the intervention) as well as the magnitude of changes in the effective contact rate, but time periods in the order of many months or several years can result under a range of reasonable scenarios.
Competing interests: No competing interests