Pathogen Identification

Identification of endemic lineages of Vibrio parahaemolyticus causing regional outbreaks and their occurrence in New Hampshire shellfish waters

Cheryl Whistler, Associate Professor of Molecular, Cellular and Biomedical Sciences, UNH (603.862.2359) and Vaughn Cooper, Associate Professor of Microbiology and Genetics, UNH (603.862.3422)

An overarching goal of Whistler and Cooper's work is to understand how changing climate influences the spread of invasive pathogens or the emergence of pathogens from endemic populations in the Great Bay Estuary of New Hampshire. Vibrio parahaemolyticus is an environmentally transmitted emergent human pathogen that can cause severe gastroenteritis when consumed in uncooked or improperly handled seafood. Vibrio diseases in general have the notoriety of exhibiting the single greatest increase (116%) in rates of infection from those observed in the mid 1990s, according to the Centers for Disease Control and Prevention. In recent years, there have even been several well publicized outbreaks from oyster harvested in the Gulf of Maine, specifically in Cape Cod. Although climate change is only one variable that may have led to these outbreaks and the general increased incidence throughout the U.S., there is a wealth of data suggesting changes in environmental conditions that increase water temperatures and alter salinity can promote disease outbreaks and epidemics.

Even as New Hampshire has escaped recent outbreaks of V. parahaemolyticus, it is unlikely that it will remain untouched. When outbreaks do occur, the response can be reactionary, and even temporary closures, especially if they receive media attention, could stifle the growing New Hampshire oyster farming industry. One of the greatest obstacles to preventing outbreaks caused by pathogenic V. parahaemolyticus is the inability to discriminate between harmless strains and those that may cause infection if consumed. Whistler and Cooper have obtained every archived outbreak strain from Mass., N.H., and Maine allowing the identification (whether endemic or invasive) of strains causing infections in the region. This is an invaluable reference and combined with their existing collection of strain type data for the Great Bay Estuary of New Hampshire, funded in part under a previous Sea Grant project, it will allow Whistler and Cooper to identify which community members are potentially the greatest threat.

Characterization of strains from local outbreaks may allow the identification of traits useful in surveillance, and also allow the future development of forecasting for the region. This study will allow New Hampshire to prepare for and minimize the impacts of climate change on public health, and protect a sensitive growth industry.

Find out more in this UNH News story about Whistler's Vibrio research.