Demographic screening for MRSA may compromise the effectiveness of ring fencing on a joint replacement unit.

Ring fencing of joint replacement (JR) units has been reported to reduce infections and is recommended by health authorities in Australia and the UK. It has not been determined whether a demographic risk assessment is adequate to prevent the admission of patients colonized with meticillin-resistant Staphylococcus aureus (MRSA) to ring-fenced units. As such, 250 admissions to the JR unit of a suburban Sydney hospital were screened, and MRSA colonization was identified in 2.8% of patients complying with the demographic risk assessment. Demographic risk assessment is not an adequate substitute for physical MRSA screening, and undermines the effectiveness of ring-fencing procedures.