Decreasing healthcare-associated infections (HAI) is an efficient method to decrease healthcare-associated Methicillin-resistant S.aureus (MRSA) infections Antimicrobial resistance data from the German national nosocomial surveillance system KISS

Data from 103 ICUs with ongoing participation during the observation period were included. The pooled incidence density of nosocomial MRSA infections decreased significantly from 0.37 per 1000 patient days in 2001 to 0.15 per 1000 patient days in 2010 (RR = 0.40; CI95 0.29-0.55). This decrease was proportional to the significant decrease of all HCAI during the same time period (RR = 0.61; CI95 0.58-0.65).The results underline the need to concentrate infection control activities on measures to control HCAI in general rather than focusing too much on specific MRSA prevention measures. MRSA rates (proportions) are not a very useful indicator of the situation.Methicillin resistant S. aureus (MRSA) is the major focus of public awareness of healthcare-associated infection (HCAI) problems in many countries and surveillance should support the work toward decreasing nosocomial MRSA infections. However, by analysing the data of the intensive care unit (ICU) component of the German national nosocomial infection surveillance system (KISS), we have observed a steady increase in the MRSA rate as a percentage of nosocomial MRSA infections among all nosocomial S. aureus infections from 2001 to 2005 and only a slight decrease in the period from 2006 to 2010. The objective of this study was to investigate the development of the incidence density of nosocomial MRSA infections during the observation period, because this is the crucial outcome for patients.The ICU surveillance method used in KISS is almost identical to the method used by the National Healthcare Surveillance Network (NHSN) for surveillance of HCAI in ICUs [1], [2]. Participation in KISS is voluntary and results are handled confidentially. HCAI are mainly registered by infection control practitioners but also by physicians. They are trained in KISS methodology and in applying CDC definitions for HCAI. The number of participating ICUs has increased from year to year. Up to 2004, the ICUs received their data twice a year to