SIST EN ISO 23418:2022 PDF

Overview

EN ISO 23418:2022 - "Microbiology of the food chain - Whole genome sequencing (WGS) for typing and genomic characterization of bacteria" - defines minimum requirements and guidance for generating, analysing and managing bacterial WGS data in the food chain. Published as an ISO/CEN standard in 2022, it covers the full WGS workflow from culture handling and DNA extraction through sequencing, bioinformatics, metadata capture and sequence repository deposition, plus validation of end-to-end workflows.

Key topics and technical requirements

• Scope of application: Bacteria isolated from products for human consumption, animal feed, food/feed production environments and primary production.
• End-to-end WGS stages (explicitly addressed):
  • Handling of bacterial cultures and axenic genomic DNA isolation
  • Library preparation, sequencing, raw-read quality assessment and storage
  • Bioinformatics analysis for genetic relatedness, genetic content and phenotype prediction
  • Metadata capture and deposition to sequence repositories
  • Validation and verification (fit-for-purpose) of workflows
• Bioinformatics subjects:
  • SNP analyses, MLST including cgMLST/wgMLST, k-mer distance analysis
  • Target gene detection (e.g., resistance or virulence markers)
  • Phylogenetic tree/dendrogram generation and interpretation
  • Requirements for software, pipeline validation, logging and metrics
• Laboratory operation and quality:
  • Sample preparation, storage, DNA isolation, library prep, use of controls
  • Raw read quality metrics, sample/data retention, laboratory environment and competence
  • Standard operating procedures, LIMS and nonconforming work handling
• Metadata & repositories:
  • Metadata interoperability, ontologies and the ISO WGS Slim reference
  • Metadata fields for sample collection, isolate history and sequencing details
  • Guidance on depositing sequences in public repositories

Practical applications and users

• Who uses it: food and feed testing laboratories, public health microbiology labs, regulatory agencies, food producers’ QA/QC teams, veterinary diagnostic labs and research groups performing WGS on bacterial isolates from the food chain.
• Practical uses:
  • Outbreak investigation and source attribution using high-resolution typing
  • Surveillance of antimicrobial resistance and virulence genes
  • Compliance, traceability and verification of sanitation/production controls
  • Standardized data exchange and long-term sequence archiving

Related standards and references

• ISO 23418:2022 aligns with CEN/ISO microbiology activities and references metadata best practices such as ISO WGS Slim and other international WGS guidance. It is intended to be implemented alongside laboratory accreditation and data governance standards to ensure reproducibility, interoperability and regulatory acceptance.

Keywords: EN ISO 23418:2022, whole genome sequencing (WGS), food chain microbiology, bacterial typing, bioinformatics, metadata, sequence repositories, validation.