Identification

Identification of various gram negative pathogens within the families Enterobacteriaceae, Vibrionaceae, Aeromonadaceae & Yersiniaceae spp (excluding Y. pestis), through a combination of MALDI-TOF, 16S rRNA Sequence analysis and (where applicable) biochemical substrate utilization tests.

Isolate (pure culture) from urine, stool, blood, environmental, food, other.

Isolate provided on appropriate culture medium with visible growth. Samples can also be submitted under frozen conditions provided they are shipped in appropriate media to survive transport.

Send as growth on appropriate culture medium or in appropriate transport medium. Frozen samples should be shipped on dry ice or other method to ensure they remain frozen.

Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.

Gastroenteritis, septicemia, infection, other.

Completed Enteric Diseases requisition form.

N/A

MALDI-TOF MS (Bruker Biotyping): MALDI-TOF results analysed using the most current Bruker Biotyper (or supplemental, in-house derived) database (Not accredited to ISO/IEC 17025 at this time).

16S rRNA gene sequencing: Sequences compared to the 16s rDNA database of known reference sequences in publically-available databases in NCBI (Genbank) and clustered (using BioNumerics or other tools)

Phenotypic Identification (Biotyping): Comparison of observed (phenotypic) reactions from a panel of substrate utilization tests against published expected reactions. Used for Vibrio spp., Yersinia spp. (excluding Y. pestis) and (in rare instances) for gram negative enteric pathogens.

*Whole genome sequencing (in-silico) based methodologies may be applied to aid in final identification (Not accredited to ISO/IEC 17025 at this time)

Note: All isolates identified as Vibrio cholerae will be referred for serotyping, subtyping and toxin testing.

For clinical diagnostic or outbreak samples*: 28 calendar days.

For surveillance or research samples*: 3 months

*Please indicate on requisition if identification is for i) clinical diagnostic or outbreak OR ii) surveillance or research application.

Please note that for poor or slower growing organisms reporting of results may be delayed beyond listed turnaround times.

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