Authors: Anthony D. Hitchins (ret.) and Karen Jinneman and Yi Chen
- April 2022: Section E.2 correction to additives amounts; Section J. clarification on enumeration homogenate preparations
- February 2022: Section E.2, correction to additives amounts; Section J, clarification on enumeration homogenate preparations; editing of other sections.
- March 2017: Addition of the sample matrix for environmental samples.
- January 2016: More specific sample preparation and analytical set-up instructions for qualitative detection or quantitative enumeration.
- January 2016: Reorganization and editing of all sections.
- February 2013: update to Table 1; update for BAM Media M52: buffered Listeria enrichment broth (BLEB) in the Media section.
- November 2011: Addition of PCR confirmation for Listeria monocytogenes and Listeria spp. isolates other than L. grayi.
- April 2011: Section E. Diagram describing the Henry Optical System for examination of colonies added; references for Listeria monocytogenes Risk Assessment and Guidance updated.
- August 2002: Section J. Enumeration: Added instructions for positive result on all MPN tubes.
- April 2001: Section H. CAMP test: Updated address for ATCC and added a link to its web page.