1 The Babies Hospital and the Department of Pediatrics, Columbia University College of Physicians and Surgeons.
Data presented demonstrate that members of H. influenzae type B populations are not uniformly sensitive to streptomycin. Over 99% are susceptible to 1.6 µ./ml.; the larger the population, the wider the variation in resistance of the small fraction surviving.
The injurious action of streptomycin on H. influenzae type B is primarily bactericidal.
Streptomycin in concentrations between 10 and 100 µ./ml. exerts a rapid lethal action; the greater the concentration of the antibiotic, the greater the speed. Significant increases in population size increase the time required for bactericidal action.
The data presented suggest that when streptomycin is used in the treatment of H. influenzae infections in man, its intramuscular administration over a period not longer than 24 hours will ordinarily suffice to obtain a maximal streptomycin effect; that in cases of meningitis the addition of a single intrathecal dose of streptomycin of 25 mg. will be adequate; and that the use of suifadiazine as an adjuvant is advisable to bring under control the eventual resistant mutants which may survive the bactericidal action of streptomycin.
Submitted on September 16, 1948