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BBL™ CHROMagar™ Listeria is a selective medium for the isolation, differentiation and identification of Listeria monocytogenes and L. ivanovii from food and environmental samples.

BBL CHROMagar Listeria has been validated by the AOAC™ Research Institute under the Performance Tested Methods^SM Program for the analysis of raw ground beef, smoked salmon, lettuce and Brie cheese when using FDA BAM, USDA FSIS, AOAC and ISO methods^1-4 with no confirmatory biochemical tests required for the identification of Listeria monocytogenes / L. ivanovii.

Confirmatory testing of isolates from food matrices other than those that have been validated, and from environmental samples, is recommended.

Listeriosis is a foodborne illness caused by L. monocytogenes. It is of particular concern for immunocompromised patients: cancer, HIV, pregnant women, neonates and the elderly. Because of the severity of the disease, 20 deaths per 100 cases, listeriosis is a serious public health and agrifood industry concern. Illness caused by L. monocytogenes has been associated with deli meats, poultry, soft cheeses, ready-to-eat seafood, smoked fish, hot dogs, salad greens and inadequately or unpasteurized milk.^5,6 L. ivanovii, rarely found in foods, is pathogenic to animals and some cases of human listeriosis have been associated with this organism.⁷

BBL CHROMagar Listeria is intended for the isolation, differentiation and identification of L. monocytogenes and L. ivanovii based on the formation of blue-green colonies surrounded by an opaque, white halo. The addition of a chromogenic and a phospholipid substrate in the medium facilitates the detection and differentiation of L. monocytogenes and L. ivanovii from other Listeria species and organisms.

An advantage BBL CHROMagar Listeria has over recommended traditional media, such as Modified Oxford and Oxford, is the ability to distinguish L. monocytogenes and L. ivanovii from other Listeria species. This facilitates the detection of L. monocytogenes / L. ivanovii in the presence of other Listeria species and other bacterial flora that may be present in a sample, thereby minimizing the risk of not detecting L. monocytogenes or L. ivanovii.

Studies using BBL CHROMagar Listeria for testing a variety of food and environmental samples demonstrated 99-100% sensitivity and 100% specificity with a detection level of 1-18 CFU/25 g. See Performance Characteristics.

Examine plates for signs of deterioration as described under "Product Deterioration." Check performance by inoculating a representative sample of plates with pure cultures of stable control organisms that produce known, desired reactions. The following test strains are recommended:

Quality Control requirements must be performed in accordance with applicable local, state and/or federal regulations or accreditation requirements and your laboratory's Quality Control procedures.

For Laboratory Use.

If excessive moisture is observed, invert the bottom over the off-set lid and allow to air dry in order to prevent formation of a seal between the top and bottom of the plate during incubation.

Protect from light during drying. See Storage Instructions.

Pathogenic microorganisms, including Listeria monocytogenes, may be present in food samples. Observe aseptic techniques and established precautions^8,9 against microbiological hazards throughout all procedures. After use, prepared plates, specimen containers and other contaminated materials must be sterilized by autoclaving before discarding.