欧洲疾控中心-2023年欧盟-欧洲经济区和欧盟扩大国家单核细胞增生李斯特菌分型的第十个外部质量评估方案（英）_69页_2mb

The tenth external quality assessment (EQA-10) for Listeria monocytogenes typing, organised by ECDC and managed by Statens Serum Institut, involved 21 laboratories across EU/EEA countries. The EQA aimed to assess the accuracy of serotyping and molecular typing-based cluster analysis.

Key findings indicate a shift towards molecular serogrouping, with an average performance of 95%. PFGE was less discriminatory but still useful when complemented with WGS. Most laboratories correctly identified clusters using WGS data, though borderline strain variants posed challenges. QC assessments were robust, despite disagreements on thresholds for acceptability.

Molecular typing-based cluster analysis saw improved participation, with 17 labs using WGS-derived data and one using SNP analysis. Challenges included inconsistent handling of QC issues and submitting errors. Data discrepancies highlight the need for harmonised QC metrics.

The report concludes that molecular serogrouping is now best practice. Recommendations include developing standard QC criteria, exploring submission formats, improving EQA strain descriptions, and addressing QC parameter variability.