Mopping Up MRSA

Editorial Note: The following are excerpts from a presentation by Dr. Stephanie Dancer.


Why the debate about MRSA and hospital cleaning?

  • “There is no evidence” – cleaning has never been regarded as an evidence-based science
  • Aesthetic considerations make cleaning difficult to assess
  • No way of measuring the cleaning process or its impact on the environment
  • Confounded by maintenance deficits
  • It costs money
  • We cannot see the enemy
  • Cleaning has always been taken for granted

No Evidence?

Just because there is no direct evidence linking surface level hygiene and MRSA acquisition, doesn’t mean there isn’t any. There is evidence for every stage of the staphylococcal transmission cycle between man and his environment.


“Frequently used hand-contact surfaces are high-risk surfaces, e.g. door handles, toilet handles, waste bin lids, telephone handsets, nurse-call buttons, infusion pump switches and computer keyboards.The closer the surface is to a patient, the more critical it is likely to be.”


Source: Application note – Biotrace (2003)

How clean are hospital surfaces?

  • 82-91% Visually clean
  • 10-24% ATP clean

Source: Griffith CJ et al, J Hosp Infect (2000)

Microbiological standards for surface hygiene in hospitals

  1. There should be <1cfu/cm2 specific organisms* in the clinical environment
  2. The Aerobic Colony Count from a hand-touch surface should be <5 cfu/cm2

This standard is based upon food industry counts as applied to food preparation surfaces but could be used for frequent hand-touch surfaces in hospitals.


*Specific organisms such as S. aureus, MRSA, C. difficile, E. coli 0157, VRE, Salmonella, etc.


Source: Dancer S, J Hosp Infect (2004)

“Are hand-touch sites routinely cleaned? Routine cleaning practices were assessed by applying a fluorescent solution to different sites in side-rooms. These sites were evaluated following patient discharge; a site was considered cleaned if the fluorescent material was removed or substantially disrupted. Although 40% of sites were cleaned properly, they tended to be the more traditional sites (toilets and sinks) whereas sites such as telephones, doorknobs and other hand-touch surfaces were scarcely cleaned at all.”


Source: Briggs & Carling, Am J Infect Control (2006)


Why do we need to look at cleaning  standards?

  • The pathogens of interest are widespread; they occur with considerable variation in time and space.
  • Finding >5 cfu/cm2 from a hand contact surface suggests that there has been insufficient cleaning.
  • A heavy microbial burden may mask the isolation of a pathogen.
  • Specific organisms suggest an increased chance of finding an epidemiologically-related pathogen, e.g. skin staphylococci and MRSA.


Staff will never wash their hands!

  • ‘Rates of hand disinfection associated with glove use, patient isolation and changes between exposure to various body sites…[indicated]…overall compliance for hand disinfection was 22% from nearly 600 opportunities for hand hygiene.’

Source: Kim PW et al, AJIC 2003

  • “The effects of exemplary hand hygiene are eroded if the environment is heavily contaminated with MRSA.”

Source: Farr et al, LI D (2001)

MRSA is the best indicator of hospital hygiene

  • “MRSA is not stronger than hospital hygiene … if you control MRSA, you control all the other organisms as well.”

Source: Wagenvoort JHT Eurosurveillance (2000)



  • There is an association between MRSA and inadequate hospital cleaning, but we need to be smart about which sites need cleaning.
  • If we don’t have some way of measuring how clean a hospital is, we will never be able to assess the importance of environmental hygiene.
  • Beware the miracle cure; our defense against dirty hospitals is hard work. Do we really have to wait for more evidence?

Formerly a consultant microbiologist at the Southern General Hospital in Glasgow, Scotland (2005-7), Stephanie now works in NHS Lanarkshire and is the current editor of the Journal of Hospital Infection. She trained at St. Bartholomew's hospital in London (1977-83) followed by postgraduate studies in Pathology at Guy's hospital, where she produced a thesis on the epidemiology and biochemistry of toxin-producing staphylococci. She has worked in various remote areas of the world, including Papua New Guinea, Thailand, Vietnam and the Canadian High Arctic, where she resuscitated 30,000 year old organisms from glacial ice. She spent six years as the Infection Control Officer for Argyll before moving to Health Protection Scotland as their inaugural microbiologist (2002-5). There she set up MRSA surveillance for Scotland, evaluated real-time PCR for the rapid identification of MRSA and helped establish the Scottish Microbiology Forum. She has been an active member of several national working groups on antibiotic prescribing and hospital cleaning, and was a formal referee for the Scottish Health Technology Assessment on MRSA screening. At present she balances clinical and editorial duties with various research projects, specifically the role of antibiotics, screening and cleaning in the control of MRSA.


Dr. Stephanie J. Dancer

Department of Microbiology
Hairmyres Hospital,

Eaglesham Road, East Kilbride G75 8RG, UK.

Tel +44 (0)1355 585000

[email protected]