Vibrio vulnificus: Death on the Half Shell
James Oliver, UNC - Charlotte
29 Mar 2013
In the USA, 95% of all seafood-related deaths are due to a single bacterium, Vibrio vulnificus. With a fatality rate exceeding 50%, it is by far the most fatal food-borne disease in the world. In this presentation I will describe the two forms of human disease (ingestion/septicemia and potentially fatal wound infections) this estuarine-inhabiting pathogen causes, and discuss the organism's virulence factors which allow disease production. We now know that there are two genetic forms of this bacterium, and these genotypes will be characterized, along with our recent whole genome sequencing studies. I will then switch from the disease to characterizing the distribution and ecology of the bacterium (concentrating on water and oysters), and describe the two key environmental factors (salinity and temperature) that influence its distribution. That discussion leads to the recent drought suffered in the Carolinas and the consequences of the resultant high salinity on V. vulnificus distribution, and on the low temperature-induced entry of the cells into the "viable but nonculturable" (VBNC) state. These points are highlighted by in situ gene expression studies. Finally, I will discuss briefly the consequences of global warming on the worldwide distribution of V. vulnificus and its disease.