STTR Phase I: Feasibility of a two-phase test tube assay for rapid detection and enumeration of Vibrio vulnificus and Vibrio parahaemolyticus in oysters

The broader impact/commercial potential of this Small Business Technology Transfer (STTR) project will be the development of a detection assay to reduce the incidence of Vibrio-related infections. Infections from Vibrio parahaemolyticus and Vibrio vulnificus are the leading causes of seafood-borne infections and fatalities, respectively, and stem primarily from raw oysters. Development and implementation of rapid, accurate, inexpensive and easy-to-use testing methods would expand Vibrio data collection and enhance preventive measures by state shellfish labs (monitor harvest areas), and oyster processors and post-harvest processors (quality control at facilities). The assays will be available to users in simple, ready-to-prepare kits. These kits will make it easy for non-specialized personnel to test oyster lots still under refrigeration without disrupting logistics, and help U.S. oyster processors and post-harvest processors improve risk management tools and access export markets with restrictions on Vibrio levels. The tests also will improve environmental risk evaluations for harvest areas by state shellfish labs, FDA, National Oceanic and Atmospheric Administration, and other members of the National Shellfish Sanitation Program. The tests will be marketed in the U.S., and other large oyster producing nations. This STTR Phase I project proposes to develop two-phase, thermostable test tube media formulations for the detection and enumeration of pathogenic V. parahaemolyticus, total V. parahaemolyticus, and V. vulnificus in oysters. The goal is to demonstrate a) > 95% sensitivity and specificity of each test with pure cultures and oyster samples; b) 24-hr detection time; c) ease-of-use of the ready-to-prepare kits, based on time, steps, equipment, materials and feedback from industry; and d) low cost. The main technical hurdles are: 1) Increasing formulation volumes for test tube assays since linear increases of agar layer volumes in test tube media formulations could impact Vibrio organism motility, and consequently detection speed and accuracy; and 2) replacing a non-heat stable antibiotic component, Polymixin B of the V. vulnificus test, with a heat stable alternative, like ampicillin or lincomycin, to improve ease-of-use. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.