Exactly, the USDA reports 100% accuracy in identifying all six Listeria species except the non-human pathogen L. Seeligeri.The USDA has never reported that the MIT1000 is marginal. Never, not once, ever. Period. L. Seeligeri is not a major human pathogen, there has been only one reported illness ever with L. seeligeri and this was in an immunocompromised patient. Nor is Aeromonas a major food pathogen, as pointed out by HKipp1 who has previously published a paper describing the organism. Anyone can read the report for themselves and then decide who is factual. I trust the USDA data and certainly not the incorrect biased conclusions of some others.
From the USDA report:
Methods that can rapidly confirm the identification of foodborne pathogens are highly desired. The USDA has recently entered into a collaborative research agreement with Micro Imaging Technology to evaluate their MIT 1000 microbial identification system for its ability to identify Listeria species including the human pathogen, Listeria monocytogenes. The MIT 1000 is a benchtop instrument that detects laser light (660 nm, 30 mW, 100 'm diameter) scattered from individual bacterial cells, in aqueous suspension, with an array of 35 individually addressed photodiode detectors. Identification is based upon pattern recognition by the automated algorithm-based comparison of averaged scattered light signal and bacteria scatter pattern libraries. Identification times are less than 10 min (often ca. 5 min) and operating costs are extremely low since the detection procedure requires no reagents (e.g., external labels or tags) other than filtered water. Cursory investigations at a USDA research lab have demonstrated the MIT 1000 to have an accuracy of 100% (n=10-30 per species) for the identification of all Listeria spp. with the exception of L. seeligeri. L. seeligeri was only identified with an accuracy of 10% and the reason for this anomaly is currently unknown. Initial attempts at false positive testing have resulted in 0% of incidence for Citrobacter freundii, Brocothrix thermospacta II, Salmonella enterica serovar Typhimurium, Escherichia coli K12, and multiple strains of E. coli O157:H7. However, a 50% false positive rate was observed for Aeromonas hydrophila when tested against the Listeria spp. library. With further development, the MIT 1000 appears to hold promise for use by food producers and regulatory agencies in the microbial testing of foods.
