[Bacterial antagonism of oral secretions towards staphylococci]. / Aspetti di antagonismo batterico nelle secrezioni orali nei confronti degli stafilococchi.

Bacterial antagonism may be one of the mechanism which regulates the bacterial flora of the pharynx. We have investigated the bacterial antagonism exerted in oral secretion by alpha-hemolytic streptococci against S. aureus and S. epidermidis. We cultured viridans streptococci and staphylococci in human saliva and we noted a bactericidal activity towards staphylococci. Such activity, referable to the salivary system (peroxidase-thiocyanate) activated by hydrogen peroxide produced by streptococci, was greater on S. epidermidis. The remarkable sensitivity of S. epidermidis could explain the rare presence of this species in pharynx and oral cavity.

[Preferential staphylococcal colonizing site in the upper airway]. / Sede preferenziale di colonizzazione degli stafilococchi nelle vie aeree superiori.

150 healthy individuals and 162 tonsillopathic patients were investigated for the presence of Staphylococcus species in the upper respiratory tract. S. epidermidis was isolated from the throat in a very small percentage of all the people examined. A great number of healthy individuals (40%) and of patients (70%) were colonized by S. aureus either in the nose or in the throat; 30% of the carriers harboured S. aureus exclusively in the tonsils and in the pharynx.