Long-term efficacy of a program to control methicillin-resistantStaphylococcus aureus

The long-term efficacy of a program to control methicillin-resistantStaphylococcus aureus (MRSA) was evaluated in a 350-bed university hospital. Three periods were monitored: pre-epidemic (January 1989–November 1989), outbreak (December 1989–June 1990) and control program (July 1990–December 1992) periods. Control measures included cohort isolation, patient care measures and therapy (oral cotrimoxazole plus fusidic acid ointment) of MRSA carriage in patients, roommates and personnel. A total of 117 MRSA-infected patients were detected. For each period respectively, MRSA incidence (number of cases per 1,000 patient-days) was 3.2, 8.2 and 2.0 in the intensive care unit (ICU) and 0.08, 0.23 and 0.26 in the general wards. During the outbreak there was a 2.7-fold overall increase of baseline MRSA incidence (p<0.02). The crude mortality was 68 % and the attributable mortality was estimated to be 50 %. The program was estimated to have prevented 76 % (CI95 28–91, p<0.0001) of expected MRSA cases and 85 % (CI95 62–94, p<0.0001) of expected fatalities due to MRSA in the ICU, but it had no significant effect in the general wards. The program did not control vancomycin consumption.