Reduction in methicillin-resistant Staphylococcus aureus infection rate in a nursing home by aggressive containment strategies.

For the month of October, 1993, the Methicillin-Resistant Staphylococcus aureus nosocomial infection rate in our 42-bed Extended Care Unit/Nursing Home was 33% (8.5% for the 1993 year). Our facility was committed to decrease colonization and infection rates and to prevent the introduction of additional colonized patients into the closed environment. Methicillin-Resistant Staphylococcus aureus containment practices were instituted and consisted of total population and staff surveillance, aggressive containment measures and followed by maintenance containment protocols. The aggressive plan included contact isolation, baths with chlorhexagluconate, treatment of nasal carriers with mupiricin and treatment of both colonized and infected patients. This was followed by maintenance measures of screening new admissions for Methicillin-Resistant Staphylococcus aureus with contact isolation and treatment for positive as described during the aggressive phase. Total population surveillance was repeated after one year. Results showed that no employees were colonized with Methicillin-Resistant Staphylococcus aureus. The initial colonization rate in residents/patients was 52%. After one year the colonization rate dropped to 2% and the infection rate to 1.4%. Molecular epidemiology demonstrated that there was limited acquisition of new strains of Methicillin-Resistant Staphylococcus aureus within the Extended Care Unit. The process was shown to be cost effective. Aggressive containment practices applied to a nursing home with a high Methicillin-Resistant Staphylococcus aureus infection rate not only reduced rates of colonization, but also markedly reduced infections. This reduction was maintained over time.