Controlling methicillin-resistant Staphylococcus aureus by stepwise implementation of preventive strategies in a university hospital: impact of a link-nurse system on the basis of multidisciplinary approaches

Abstract

Background: Current approaches in the control of methicillin-resistant Staphylococcus aureus (MRSA) in the large tertiary referral hospital have not been universally successful.

Methods: The trend of MRSA rates and their relationship with stepwise implementation of preventive strategies in Tokai University Hospital during a 76-month period from September 1998 to December 2004, was retrospectively analyzed with a quasi-experimental design.

Results: Implementation of strategies including a feedback process with case and epidemic reporting, an infection control team and office, and a preventive guideline for MRSA did not result in reduction in monthly MRSA rates in the hospital, as analyzed with Shewhart u charts. When infection control link nurses were organized and their activities became full-scale, there appeared significant reduction in arithmetic mean of the monthly rates of MRSA from 6.3% to 5.0% in June 2002. Meanwhile the mean values for monthly counts of new MRSA cases also dropped in 15 of 25 wards/units in June 2002, as analyzed with Exponentially Weighted Moving Average charts. Concurrently, there was a significant increase (17.3%) in the monthly consumption of handwashing liquid plain soap. Thereafter the MRSA rates remained low for 2 years within three standard deviations.

Conclusions: The sustained reduction of MRSA rates in the hospital can be related to introduction of the infection control link-nurse system on the basis of continuous enforcement of basic and multidisciplinary approaches such as hand-hygiene compliance.