[Evaluation criteria of antitubercular drugs from microbiological view]

In the years from 1954 to 74 sensitivity tests with about 12 000 strains of tubercle bacilli isolated from patients have been performed by the serial dilution method. From the results of the tests shown in the table one can see a remarkable shift in the frequency of strains sensitive against the so-called major drugs Streptomycin and INH, whereas only slight variations have occurred with the recent drugs Ethambutol and Rifampicin. The well known change of clinic and epidemiology of tuberculosis in the past two decades is indeed accompanied by changed results of microbiological tests. In conclusion the present chemotherapeutical situation proves much better than in 1954: to-day a more sensitive and even smaller reservoir of mycobacterium tuberculosis is facing twice as much highly effective drugs than formerly.