EFFECT OF PENICILLIN ON GROUP A STREPTOCOCCI IN VIVO IN THE ABSENCE OF LEUCOCYTES 1

Abstract

When 4-hour cultures of group A streptococci are incorporated in the center of agar disks and implanted in the peritoneal cavity of the rabbit, the organisms enter immediately the logarithmic phase of growth and continue to multiply at maximal rates for 8 hours. Subsequently a plateau is reached and persists for 5 days. Large amounts of penicillin given prior to or within 5 hours of implantation kill the bacteria promptly, but when given 12 hours or more after implantation, the drug fails to sterilize the foci. Although repeated administration decreases the bacterial count, some viable organisms persist. Implications of these findings on the treatment and sequelae of streptococcal infection in man are discussed.