Detection of Escherichia coli O157:H7 in select foods using the BAX® System E. coli O157:H7 MP
Background: This highly-specific qualitative analysis, will detect if only one E. coli O157/H7 cell is present, therefore resulting in a negative or positive result. This assay does not tell you how much of the pathogen is present.
Standard sample sizes are one swab, or 25g of food. Representative sample portions are collected from sample submitted, mixed with highly selective enrichment media and incubated for 12 hours (depending on sample size and matrix). After incubation, cells from the sample enrichment are broken open (lysis) to expose their DNA, which, if the target E. coli O157/H7 DNA is present, will be copied thousands of times (amplification), allowing for detection via the BAX-PCR E. coli O157/H7. assay.
The BAX System uses DNA-based technology specific to E. coli O157/H7 to provide next-day results that are reliable and reproducible, allowing food producers and processors to quickly and accurately release safe products to the market.
If the test is positive for E. coli O157:H7, a quantitative analysis (MFHPB-10) must be performed on the same sample to confirm for the presence of the pathogen.
Method: Health Canada (MFLP-30)
Turn Around time: 1 Business Day
Reportable results: Negative or Positive of food sample or swab
SPECIMEN REQUIREMENTS
Container/Kit: Submit 250 grams of food in a sterile plastic sample bag with round wire closure or swab.
Collection information: See Section Sampling under Food Sampling.
Requisition: Complete all fields of the form. See section Forms under Microbiology Sample Sheet.
Sterile Bag: See section Form under Requisition for Containers and Supplies.
Limitation:None.
Preparation prior to transport: Keep refrigerated or frozen.
Shipping Instructions:
- Ship all foods in containers with hard walls and lids secured in the closed position.
- Shipping containers must be labelled with the submitting organization, unique identifier and contents e.g. FOOD SAMPLES on the outside of the container.
- Shipping containers used for food samples should be dedicated to food samples and not be used for other types of environmental samples.
- Ship dry foods and other shelf stable foods at ambient temperature in a closed container.
- Ship frozen foods in an insulated container with sufficient dry packs to maintain the frozen state.
- Ship perishable foods in an insulated container with sufficient cold packs to maintain a temperature as close to 4°C as possible. If ice is used, contain the ice in a manner that does not allow water contact with the samples.
- Submit all food samples to the laboratory as soon as possible
TEST INFORMATION
Escherichia coli O157:H7 should be absent.