BIOLOGICAL PROPERTIES OF STREPTOCOCCI UNDER CONDITIONS OF EXPERIMENTAL STREPTOCOCCAL INFECTION

Abstract

The occurrence of asymptomatic carriage, as well as of clinically manifest streptococcal infection in patients receiving penicillin preparations, is usually regarded as a consequence of streptococcal superinfection. At the same time, data from experimental studies devoted to the variability of haemolytic streptococci during the development of their resistance to and dependence on penicillin suggest the possibility of prolonged persistence of streptococcus in the body of a patient receiving antibiotics. Blood cultures performed simultaneously with the bacteriological examination of the chamber contents were sterile in all cases; at the same time, streptococcal antigen was present in the blood serum of the overwhelming majority of the experimental and control animals. Characteristically, streptococcal antigen and an increase in its titre were noted not only in the control but also in the experimental rabbits at late periods, when bacteriological examinations were, as a rule, unproductive.