Recurrent staphylococcal infection in families.

This controlled double-blind study examined the efficacy of a single large inoculum of Staphylococcus aureus 502A in interrupting intrafamilial spread of recurrent staphylococcal abscesses. Forty families were enrolled in the study and 32 completed six months of follow-up care. All participants were first treated with oral oxacillin sodium or dicloxacillin sodium, twice daily hexachlorophene showers, and bacitracin given nasally for two weeks. Some then received nasal inoculation of 10(8) to 10(9) organisms of S aureus 502A while others were given only sterile broth. Fifteen of 17 families or 29 of 36 individuals who received 502A remained free of recurrence for six months of observation, while only four of 15 control families or 18 of 34 members had no recurrences (P less than .005). After six months after colonization, 83% of the treatment group retained the 502A organism.