Staphylococcus aureus is a bacteria that causes serious, often life threatening infections including pneumonia, wound, and bloodstream infections. Persons with AIDS are at high risk for S. aureus infections. They are also at high risk for nasal carriage of S. aureus. In fact, nasal carriage is a known risk factor for subsequent S. aureus infection. Topical mupirocin, an antibiotic when applied to the anterior nares, is a safe, effective way to eliminate S. aureus colonization. Some studies have shown that mupirocin can also decrease the risk of S. aureus infection, but many of those studies utilized historical controls and none were rigorously tested among AIDS patients over an extended period of time.

The main purpose of this randomized, double-blinded, placebo controlled study is to determine if mupirocin can eliminate S. aureus nasal colonization in residents at PSI (inpatient, drug rehabilitation facility for AIDS patients in the Bronx.) PSI residents currently have a high incidence of S. aureus nasal colonization and infection. Nasal cultures followed by twice daily application of mupirocin vs. placebo for five days will be performed on a monthly basis for 8 months. the study will examine whether mupirocin decreases the incidence of S. aureus infections and prevents S. aureus nasal colonization. The study is important because it may show that mupirocin is an effective way to eliminate nasal colonization and prevent S. aureus infections in AIDS patients, among those at highest risk for serious S. aureus infection.

Hypothesis: Monthly application of mupirocin will reduce nasal colonization with S.aureus