An outbreak of nosocomial staphylococcal infections occurred over a six months period in an intensive care unit. This outbreak was caused by a single phage type of oxacillin resistant Staphylococcus aureus (SA) which infected ten patients. Six patients had bacteremia with infected catheter, two with urinary tract infection and two patients had a pneumonia. The median SAPS was 13. Four patients died. An epidemiologic study was performed to know SA nasal carriage prevalence of patients and hospital staff. There were seven isolates of SA from 83 hospital staff and three from 20 patients, all with the same phage type 77. Hospital staff and patients colonisation with a same SA strain is a potential reservoir for epidemic nosocomial infections. Prophylactic measures are hygienic measures like handwashing, but perhaps also patients and staff selective decontamination with topical antimicrobial substances.