Froelich Lab
George Mason University
Department of Biology
Vibrio in oysters and clams in North Carolina
The role of salinity and temperature in Vibrio concentrations in oysters
In a collaborative project that included the University of North Carolina at Charlotte, the University of North Carolina at Chapel Hill - Institute of Marine Sciences, and the North Carolina Division of Marine Fisheries, oysters were continuously collected from sites in coastal North Carolina for over two years. An easy-to-read matrix tool was developed to estimate the number of V. vulnificus cells in water and oysters in NC. This tool can be used by anyone by simply measuring the temperature and salinity of the water in which the oysters are harvested.
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An inexpensive thermometer and salinity meter (refractometer) can be purchased from the following links:
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Infrared Thermometer and Salinity Meter / Refractometer
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To use the following tool, simply measure the temperature and salinity of the water covering or around the oysters you wish to harvest. Next, simply find the point on the chart where the salinity (bottom of graph) and temperature (left side of graph) meet.
V. vulnificus in oysters
V. vulnificus in water
For example, if the measured temperature was 24 degrees celsius, and the salinity was 20 parts per thousand, the intersection of those two lines would be in the yellow region of the graph. Indicating that there are likely ~3000 V. vulnificus cells per gram of oyster meat.
For further details and methods, please refer to the publication in Applied and Environmental Microbiology
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Contributors
Jim Oliver lab at the University of North Carolina at Charlotte, Department of Biological Sciences
Brittney Phippen, Mezrop Ayrepetyan, Tiffany Williams, Leigh Robertson
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Rachel Noble lab at the University of North Carolina at Chapel Hill, Institute of Marine Sciences
Kelsey Jesser, Justin Hart, Denene Blackwood, Mary-Jo Weiss, Katie Dugan
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Brett Froelich lab at the University of North Carolina at Chapel Hill, Institute of Marine Sciences
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North Carolina Division of Marine Fisheries with the Department of the Environment and Natural Resources
Patti Fowler, Shannon Jenkins, Paul Moore, Mike Millard, Timmy Moore, Phil Piner, Steve Murphy
Products
Publications
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Datasets
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Full Data set of project available at Figshare.com DOI: 10.6084/m9.figshare.5135629
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Presentations
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Vibrio vulnificus and Vibrio parahaemolyticus in North Carolina oysters and clams, Invited Presentation to the 1st Oyster Symposium, presented by Oyster South, January 2017
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The state of Vibrio research in North Carolina; Invited Presentation to the Southern California Coastal Water Research Project, December 2016
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Clams and oysters have different Vibrio concentrations despite being harvested from the same site; Presented at the 2016 UNC Water Microbiology Conference, Chapel Hill, NC, May 2016
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Differences in Vibrio vulnificus and Vibrio parahaemolyticus ecology between clams and oysters collected from the same location, Presented at the 2016 International Conference on Vibrio; Roscoff, France
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Posters
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JD Oliver, BA Froelich, RT Noble, B Phippen; A long term study on the interaction of Vibrio vulnificus and V. parahaemolyticus with oysters and clams; Presented at the 11th International Conference on Molluscan Shellfish Safety; Galway, Ireland, 2017
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TC Williams, BA Froelich, B Phippen, P Fowler, RT Noble, and JD Oliver; Long-term assessment of V. vulnificus clinical and environmental genotype distributions in environmental samples from the North Carolina coast; Presented at the 2016 International Conference on Vibrio, Roscoff, France
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B.A. Froelich, M. Ayrapetyan, P. Fowler, J.D. Oliver, and R.T. Noble; 2015; Risk matrix tools for predicting pathogenic Vibrio spp. in oysters harvested from North Carolina; Presented at the 2015 National Institute of Food and Agriculture, United States Department of Agriculture, Washington, D.C.
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B.A. Froelich, M. Ayrapetyan, P. Fowler, R.T. Noble, and J.D. Oliver; 2014; The development of a decision matrix tool for predicting pathogenic Vibrio spp. in oysters harvested from North Carolina, USA; Presented at Vibrio 2014, Edinburgh, Scotland
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