RESUMEN
Nine strains (6%) were confirmed as resistant (MIC=20ug/ml) to methicillin (MT) among 150 isolates of staphylococcus aureus. These MT-resistant staphylococcus aureus (MRSA) strains were also turned out to be more less resistant to other antibiotics tested, such as penicillin, chloramphenicol, tetracycline, and gentamicin except for cephaloridine. It was noteworthy, however, that strain MRSA 5 showed a relatively susceptible attitude toward most of the antibiotics tested, while being extremely resistant to MT only. Salt (NaC1) containing (5-3%) media did not have any significant effect on the degree of MT-resistance of MRSA strains. There was, however, such a tendency as that by the addition of salt the degree of MT-resistance was lowered in the highly MT-resistant strains while enhanced in MT-susceptible ones. It was confirmed that penicillinase did not have any effect on the MT-resistance while most of the penicillin- resistant strains produced the enzyme.