Tackling contamination of the hospital environment by methicillin-resistant Staphylococcus aureus (MRSA): a comparison between conventional terminal cleaning and hydrogen peroxide vapour (HPV) decontamination

Guy's and St. Thomas' NHS Foundation Trust, London

(Published in French et al. J Hosp Infect 2004;57:31-37.)

Case study contributors:

Gary. L. French (Consultant Microbiologist, Guy's and St. Thomas' Hospital NHS Foundation Trust, London, UK and Professor of Microbiology, King's College London, UK), Jonathan A. Otter (BIOQUELL (UK) Ltd).

We conducted a prospective study to investigate environmental contamination with MRSA and compare the impact of conventional terminal cleaning with a novel method, HPV decontamination. We investigated environmental contamination with MRSA by surface swabbing before and after conventional terminal cleaning compared with HPV decontamination. All areas tested were contaminated with MRSA, MRSA was common in sites that might transfer organisms to the hands of staff and was isolated from areas and bed frames used by non-MRSA patients. 74% of 359 swabs taken before cleaning yielded MRSA. After cleaning, all areas remained contaminated, with 66% of 124 swabs yielding MRSA (figure). In contrast, after exposing six rooms to hydrogen peroxide vapour, only one of 85 (1.2%) swabs yielded MRSA, by enrichment culture only (figure). The process was accepted well by ward staff and was seen as a positive intervention, despite logistical considerations such as vacation of areas to be decontaminated. The hospital environment can become extensively contaminated with MRSA that is not eliminated by standard cleaning methods. In contrast, HPV decontamination is a highly effective method of eradicating MRSA from rooms, furniture and equipment. This research has prompted further work in the NHS and overseas to investigate the importance of environmental contamination and the utility of HPV decontamination.

Other information or references:

Bates CJ, Pearse R. Use of hydrogen peroxide vapour for environmental control  during a Serratia outbreak in a neonatal intensive care unit. J Hosp Infect 2005;61:364-366.

French GL, Otter JA, Shannon KP, Adams NM, Watling D, Parks MJ. Tackling contamination of the hospital environment by methicillin-resistant Staphylococcus aureus (MRSA): a comparison between conventional terminal cleaning and hydrogen peroxide vapour decontamination. J Hosp Infect 2004;57:31-37.

Jeanes A, Rao G, Osman M, Merrick P. Eradication of persistent environmental MRSA. J Hosp Infect 2005;61:85-86.
 
Johnston MD, Lawson S, Otter JA. Evaluation of hydrogen peroxide vapour as a method for the decontamination of surfaces contaminated with Clostridium botulinum spores. J Microbiol Methods 2005;60:403-411.
 
Otter J. Bio-deactivation of hospital pathogens. Health Estate 2005;59:41-44.
 
Otter JA, French GL, Adams NM, Watling D, Parks MJ. Hydrogen peroxide vapour decontamination in an overcrowded tertiary care referral centre: some practical answers. J Hosp Infect 2006;62:384-385.

Rogers JV, Sabourin CL, Choi YW, Richter WR, Rudnicki DC, Riggs KB, Taylor ML, Chang J. Decontamination assessment of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surfaces using a hydrogen peroxide gas generator. J Appl Microbiol 2005;99:739-748.