The role of the carrier state and hypersensitivity in experimental staphylococcal infections in mice.

Abstract

SUMMARY Dissemination of Staphylococcus aureus from the site of carriage into the bloodstream and its localisation at a traumatised portion of a bone were studied in four categories of mice, viz., carrier hypersensitive, carrier nonhypersensitive, non-carrier hypersensitive, and non-carrier non-hypersensitive. The provocations used were a pyrogenic stimulus, produced by intraperitoneal injection of 0.1 ml of modified Haffkine plague vaccine, and controlled trauma to the right hind leg, either alone or in combination. It was observed that transient bacteriaemia occurred during periods of induced fever or as a sequel to trauma. It is of interest that 27 per cent. of the hypersensitive carrier mice as opposed to 2 per cent. of the non-hypersensitive carriers showed positive blood culture. Among the non-carrier mice, positive blood culture was obtained from 2.5 per cent. of the hypersensitive animals only. Significantly, localisation of Staph. aureus at the injured bone was detectable in hypersensitive mice only.