FIG 1.

Survival of M. bovis BCG in prolonged stationary phase and the effect of antimicrobial treatment. (A) M. bovis BCG and M. tuberculosis were grown in sealed flasks to stationary phase and were incubated for a further 90 days. (B) One-month-old M. bovis BCG cultures were treated with antimicrobials and incubated for an additional 2 months before viability was assayed. **, statistically different from untreated control (P < 0.01; n = 5). H₂O, water control; Str, streptomycin; Emb, ethambutol; INH, isoniazid; Cer, cerulenin; MNZ, metronidazole. Mean values of five independent experiments are presented.