ELIMINATION OF STAPHYLOCOCCUS-AUREUS NASAL CARRIAGE IN HEALTH-CARE WORKERS - ANALYSIS OF 6 CLINICAL-TRIALS WITH CALCIUM MUPIROCIN OINTMENT

Six double-blind, independently randomized studies evaluated the effic acy and safety of calcium mupirocin ointment in eliminating nasal carr iage of Staphylococcus aureus among health care workers. Healthy volun teers with stable nasal carriage of S. aureus (n = 339) received eithe r calcium mupirocin ointment (n = 170) or an identical placebo ointmen t (n = 169) intranasally for 5 days. Nasal carriage was eliminated 48- 96 hours after completion of treatment in 130 (91%) of 143 evaluable v olunteers receiving mupirocin but in only 8 (6%) of 142 evaluable volu nteers receiving placebo. The 85% crude difference represents a 90% po oled (adjusted) estimate of the risk difference (95% confidence interv al, 0.86-0.95) and a risk ratio of 16 (P < .0001). This effect of trea tment with mupirocin was observed consistently (risk ratio, 8-32) in a ll six centers. In addition, 96 of the 130 mupirocin-treated volunteer s and 1 of the 8 placebo-treated volunteers who were culture-negative at the end of therapy remained free of S. aureus 4 weeks after treatme nt. Adverse events in each treatment arm were mild and equally frequen t. These data, consistent across six institutions, demonstrate that ca lcium mupirocin ointment administered intranasally for 5 days is safe and effective in eliminating stable nasal carriage of S. aureus.