The EUCAST Disk Diffusion test was developed by EUCAST under the auspices of ESCMID and with the help of many laboratories. The help of these laboratories is gratefully acknowledged. Most are listed under the EUCAST laboratory network. The work started in 2009 and is ongoing - new agents, new species, revised or new breakpoints and new resistance mechanisms necessitates constant development and recalibration.
Development of an accurate and reliable disk diffusion method requires a linear correlation between Minimum Inhibitory Concentrations (MICs) and the inhibitory zone diameters from disk diffusion tests.
The files below list material and graphs used for determining zone diameter breakpoints to match MIC breakpoints (Example 1). The files are updated yearly. For 2025, S. dysgalactiae is new.
For previous versions of documents, see the document archive.
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