The SERL introduced WGS-based typing of all Shiga toxin-producing E. coli (STEC) in August 2017. This permits the characterisation of strains and assessment of relatedness at the bacterial genome level with very high discriminatory power.
This enables us to report extra typing information such as the presence of other genes in addition to shiga toxin genes (eae, stx subtype), the full O:H serotype of E. coli O157 and non-O157 E. coli and a multilocus sequence type (ST). This extra information is communicated to diagnostic laboratories in a follow up report.
SERL performs a cluster analysis after every sequencing run and compares new data with WGS data already present in the SERL genomic database. Any matches identified by cluster analysis and occurring within the previous month are immediately communicated to the local Health Protection Teams and Public Health Scotland.
In addition, sequence data from each run is compared with sequence data produced by UKHSA from cases in England & Wales to highlight any potential UK matches.
Training & Research
SERL is actively involved in the training of BSc Honours students, healthcare scientists, health protection and infection control nurses and postgraduate medical trainees in Combined Infection Training and Public Health.
This is carried out on an ad-hoc basis and interested parties are advised to contact SERL to arrange training attachments.
SERL also participates in and collaborates on externally funded research projects.
External Quality Assurance Schemes
SERL participates in the following:
- International External Quality Assessment Scheme for typing of Shiga-toxin producing E. coli, organised by the European Food and Waterborne Diseases and Zoonoses Programme, ECDC (ECDC-FWD). The scope of this EQA covers:
- Molecular serotyping
- Virulence gene determination
- Cluster analysis using WGS
- QCMD Diarrheagenic Escherichia coli EQA covering rfbO157, stx1 & stx2 gene determination
All tests reported by the SERL are UKAS accredited to ISO 15189:2012. The NHS Lothian Department of Laboratory Medicine Compliance Manager is Nadine Wilkinson (nadine.wilkinson@nhslothian.scot.nhs.uk).