A major obstacle for the identification of virulence traits in this pathogen is the unavailability of animal models that recapitulate human disease. Therefore, we will evaluate the utility of several alternative animal models for identifying traits that contribute disease in objective 1. <P>We will then apply these models in three specific areas of inquiry in objective 2. We will test the specific hypothesis that differences in temperature regulation are useful for discriminating virulent strains among environmental strains, we will identify virulence traits in high throughput screens for virulence traits, and will compare the disease potential of a collection of environmental and clinical strains from wide distribution most notably including those from shellfish harvested in New England.<P> The most important specific outcomes of our work is the generation of a body of knowledge on virulence determinants that will aid in the development of 1) preventative measures for reducing exposure, infection and disease, 2) technologies for discriminating rare virulent pathogens from among harmless environmental strains, and 3) early detection and risk assessment to allow better management of shellfish and aquatic resources.
Non-Technical Summary: According to the Food and Drug Administration, the current limiting factor to proper risk assessment of the threat of V. parahaemolyticus is a lack of knowledge of the virulence characteristics of this organism (FDA, 2001). Thus, we cannot hope to ensure food safety without a better understanding of the basis of virulence and thus distinguishing characteristics that would allow the discrimination of pathogens from harmless environmental strains. This proposal aims at identifying virulence traits which may then translate into genetic markers for discrimination of pathogenic strains from the environment. <P> Approach: The project involves applying different known pathogenic and attenuated strains of the human pathogen Vibrio parahaemolyticus to various alternative models including fruit flies, worms, and plants and looking for differences in disease (death). Once useful models are developed, we will evaluate unknown environmental strains, and also evaluate correlation of temperature regulation with virulence potential.