Session: Poster Session: Assessing the Value of MRSA Screening
Monday, October 27, 2008: 12:00 AM
Room: Hall C
Background: Methicillin-resistant Staphylococcus aureus (MRSA) has become an increasingly important pathogen in hospitals and recently also in the community. In Dutch and Scandinavian hospitals the 'Search and Destroy' (S&D) policy is applied, which resulted in a low MRSA prevalence (<1%). In contrast, countries without control policy have reached percentages up to 50%. The objective of this study was to determine the effectiveness of the S&D policy over the years 2001 until 2006 in a Dutch teaching hospital with 1370 beds. Methods: The effectiveness of the S&D policy was based on the occurrence of nosocomial spread, determined using 1) patient’s history, 2) relation in time and place to other patients or Health Care Workers (HCW), and 3) molecular typing (PFGE and Spa typing) and expressed as reproductive rate. Results: During 2001 until 2006, 95 persons were identified to carry MRSA, i.e. 82 patients and 13 HCW. Based on PFGE typing 33 different types of MRSA were identified, i.e. eight clusters of two or more identical PFGE strains and 25 types containing one single PFGE strain. The largest strain clusters consisted of 28 strains (PFGE type 55) and 25 strains that could not be typed with PFGE (non-typeable). Owing to the absence of a link between some persons from the same PFGE cluster and the increase of non-typeable MRSA, a second typing was performed. Spa typing of the 8 PFGE clusters identified 15 different Spa types, so 7 additional types were found. Twenty-two persons (23%) were found to be colonized with MRSA by nosocomial transmission, i.e. 13 patients and 9 HCW. All were colonized with the same strain (PFGE type 55) in two outbreaks in 2003 and 2004. In 2005 and 2006, no nosocomial transmission was found. The reproductive rate in the study period was 0.30 (22 secondary cases / 73 index cases). Conclusions: The S&D policy in the Amphia hospital is highly effective in preventing nosocomial transmission of MRSA.