Abstract
A novel diffusion zone method of quantitative assay of the antibiotic sensitivity of bacterial strains was tested on freshly isolated gonococci. Smoothly variable estimates of the minimum inhibitory concentration of penicillin for these strains was obtained with sufficient accuracy and precision (coefficient of variation c. 10 per cent.) by means of a simple graphical analysis and without replication. Such estimates were free from the chief sources of error associated with the commonly applied 'incorporation' and 'diffusion' methods. The method revealed that 816 isolates of gonococci obtained in the Bristol area during a 6-month period fell into a large 'sensitive' group (MIC c. 0.02 unit per ml.) and three smaller more resistant groups, and that this pattern occurred in three widely spaced centres within the area. It is suggested that the method is capable of revealing details of distribution that may be masked by the usual techniques and that it is of wide applicability.
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Selected References
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- COOPER K. E., LINTON A. H., SEHGAL S. N. The effect of inoculum size on inhibition zones in agar media using staphylococci and streptomycin. J Gen Microbiol. 1958 Jun;18(3):670–687. doi: 10.1099/00221287-18-3-670. [DOI] [PubMed] [Google Scholar]
- LINTON A. H. Interpreting antibiotic sensitivity tests. J Med Lab Technol. 1961 Jan;18:1–20. [PubMed] [Google Scholar]
- Lynn R., Nicol C. S., Ridley M., Rimmer D., Symonds M. A., Warren C. Further studies of penicillin resistant gonococci. Br J Vener Dis. 1970 Oct;46(5):404–405. doi: 10.1136/sti.46.5.404. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stolz E., Zwart H. G., Michel M. F. Sensitivity to ampicillin, penicillin, and tetracyline of gonococci in Rotterdam. Br J Vener Dis. 1974 Jun;50(3):202–207. doi: 10.1136/sti.50.3.202. [DOI] [PMC free article] [PubMed] [Google Scholar]