Vibrio vulnificus is a pathogenic bacterium, routinely found in waters of estuarine environments as part of the normal microflora. This organism can be divided into two genotypes, a C-type associated with clinical isolation, and an E-type associated with environmental isolation. While it was previously known that C- and E-type cells were genetically distinct, a further distinction was found among C-type strains that has the potential to predict pathogenicity using simple PCR. It was also found that C- types cells are more rapidly taken up by oyster hosts than E-type cells in some cases, but that depuration was just as rapid for both types. These studies revealed that addition of laboratory grown bacterial strains can cause endogenous bacteria in oyster to resuscitate from the viable-but-non-culturable state. Inefficiencies in bacterial uptake in oysters led to a study that concludes that E-type strains are more readily integrated into marineaggregates that C-type strains. Most notably, V. vulnificus was observed to decline in North Carolina estuaries in response to a prolonged and severe drought.