Impact of livestock-associated MRSA in a hospital setting

Nienke van de Sande-Bruinsma, Maurine A Leverstein van Hall, Maria Janssen, Nynke Nagtzaam, Sander Leenders, Sabine C de Greeff, Peter M Schneeberger

The Netherlands is known for a stringent search and destroy policy to prevent spread of MRSA. In the hospital setting, livestock-associated MRSA (LA-MRSA) is frequently found in patients coming from the high density farming area in the south of the Netherlands. The aim of the study was to determine the contribution of LA-MRSA in the epidemiology of MRSA in cases found following the Dutch search and destroy policy. From two hospitals serving a population of 550,000 persons all data on MRSA cultures and subsequent control measures from 2008 and 2009 were retrospectively collected and analyzed. A total of 3856 potential index patients were screened for MRSA, 373 (9.7%) were found to be positive, 292 ( 78%) LA-MRSA and 81 (22%) non-LA-MRSA respectively. No secondary cases were found among contact research in persons exposed to LA-MRSA (0/416), whereas similar contact research for non-LA-MRSA resulted in 83 (2.5%) secondary cases. LA-MRSA were rarely found to cause infections. LA-MRSA is more prevalent than non-LA-MRSA in Dutch Hospitals in the South of the Netherlands. However, retrospectively studied cases show that the transmission rate for LA-MRSA was much lower than for non-LA-MRSA. This suggest that infection control practices for LA-MRSA may possibly be less stringent than for non-LA-MRSA.