Ecological Modeling to Identify Seasonal Conditions that Contribute to Vibrio parahaemolyticus Concentration Variation in Oysters from a New England Estuary

Vibrio parahaemolyticus is a naturally occurring bacterial species in most coastal environments that has become a persistent public health problem in the Northeast United States. Most strains are believed to be non-pathogenic... [ view full abstract ]

Vibrio parahaemolyticus is a naturally occurring bacterial species in most coastal environments that has become a persistent public health problem in the Northeast United States. Most strains are believed to be non-pathogenic and those that do cause disease are historically contracted from the consumption of seafood and shellfish from warm water environments. It is believed that co-occurring climate change associated environmental conditions may be an underlying factor behind this new disease pattern. To determine this, it is necessary to characterize V. parahaemolyticus ecology in this region. We applied general additive models and time series analysis to long term surveillance data from the Great Bay Estuary (GBE) and identified that water temperature, salinity, chlorophyll a, and pH are key environmental conditions that contribute to V. parahaemolyticus concentration variation in this regionally representative estuary. Further, non-metric multidimensional scaling and indicator species analysis identified plankton community dynamics that have similar seasonal patterns to V. parahaemolyticus and that Cheatocerus spp. are key markers for spring, summer and fall plankton communities. The application of these findings provides important new directions for characterizing the role of seasonal conditions in V. parahaemolyticus concentration variation and identifies potential targets for mechanistic studies of event-based variation. Given that the range of conditions and effect of those conditions on V. parahaemolyticus concentration can vary widely within regions, this advancement in the characterization of V. parahaemolyticus ecology will contribute to the development of region-specific forecasting systems for both public health agencies and the shellfish industry.