Reference Antimicrobial Susceptibility Testing (AST) Data

CDC programs perform AST of bacterial and bloodstream Candida isolates collected in surveillance programs and isolates submitted to CDC from the reference laboratories for susceptibility testing because of unusual resistance. CDC’s default method is frozen broth microdilution using in-house prepared panels according to standards established by the Clinical and Laboratory Standards Institute (CLSI Documents: M7 for bacteria; M27 with M60 for Candida). Etest is a reference method for antifungal susceptibility to amphotericin B in accordance with CLSI M-27e4. CDC is making these data available online for use in setting breakpoints for interpretation of antimicrobial susceptibility testing.

The downloadable workbooks contain tables and graphic representations that display MIC distributions for various bacteria and Candida. We provide a description of the isolates tested with each dataset. CDC will continue to expand this database to include data from additional bacterial and fungal isolates and data from new antimicrobial drugs.

MIC data for Neisseria gonorrhoeae isolates can be found on the CDC Division of STD Prevention (DSTDP) Antimicrobial Resistant Gonorrhea website: (Gonococcal Isolate Surveillance Project (GISP) Profiles and Annual Reports).

  • Downloadable Data & Additional Information
  • Distributions of MIC for fungi
  • Candida
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