No. of Strains Susceptibility to indicated druga RIF INH STR EMB 28 Rb R R R 4 R R Sc S 2 R R R S 1 R R S R

Table 1: Drug susceptibility patterns of MDR M. tuberculosis strains; a RIF-rifampcin; INH-isoniazid; EMB-ethambutol; STR-streptomycin, bR-resistant, cS-sensitive