The survival of four aerobic and four anaerobic pathogens was evaluated quantitatively on cotton swabs and calcium alginate swabs stored in dry tubes as compared with swabs stored in Amies Transport Medium without charcoal. Survival of the pathogens was markedly improved when stored in Amies Transport Medium, although there was considerable loss of viability after a few hours of storage.

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A rapid method for assay of antimicrobial agents in human serum was modified to provide a method for rapidly assessing the activity of antimicrobial discs being used for susceptibility testing. Each In 1969, Stroy (6) published the details of a disc diffusion technique for the rapid estimation of antibiotic concentrations in human serum. The technique she described involved the inoculation of test plates which are preincubated for 2 to 6 hr and then stored at 4 C until needed. Antibioticcontaining discs are then applied directly to the stored plates, and discernible zones of inhibition can be measured after 5 to 6 hr of incubation. We have modified this technique slightly to develop a simple, rapid method for monitoring the potency of antibiotic discs prior to each day's run. This modified control test has been used as part of our clinical laboratory's quality control system for more than 2 years, and the results are summarized in the present report.