Bacterial Interference

Nasal carriers of pathogenic strains ofStaphylococcus aureusare a potential hazard to their environment, their contacts, and themselves. At present, there is no known method which permanently eradicates "virulent" strains ofS aureusfrom the nose of all persistent carriers. These investigations were undertaken to evaluate a new approach to a solution of the problem presented by adult carriers of virulent staphylococci. Shinefield and his associates have demonstrated that colonization of the nasal mucosa of newborns with one strain of coagulasepositive staphylococcus interferes with subsequent acquisition of a second strain ofS aureus,1and that, in fact, artificial colonization of newborns immediately after birth with a staphylococcus of low virulence can be employed to protect infants from infection by virulent "epidemic" strains.2-5Epidemiologic data which would support the hypothesis of biologic competition between different strains of staphylococci have been reported by other groups of investigators.6-8 The