Recovery of interfering and β -lactamase -producing bacteria from group A β-haemolytic streptococci carriers and non-carriers

The purpose of this study was to compare the frequency of recovery of aerobic and anaerobic organisms with interfering capability against group A beta-haemolytic streptococci (GABHS) and beta-lactamase-producing bacteria (BLPB) from the tonsils of GABHS carriers and non-carriers. The presence of aerobic and anaerobic bacteria capable of such interference in vitro was evaluated in cultures obtained from the tonsils of 20 healthy children who were non-GABHS carriers and 20 who were GABHS carriers, and also from 20 children who were asymptomatic after completing a course of penicillin for acute GABHS pharyngo-tonsillitis (PT) and were non-GABHS carriers and 20 who were GABHS carriers. In healthy children, 32 interfering isolates were recovered from 16 non-GABHS carriers (1.6 per child) and 13 were isolated from 7 GABHS carriers (0.65 per child) (P