The infective dose for gastrointestinal symptoms in healthy individuals is unknown but for predisposed persons, septicemia can presumably occur with doses of less than 100 total organisms. The culturing of the organism from wounds, diarrheic stools, or blood is diagnostic of this illness. This organism has been isolated from oysters, clams, and crabs. Consumption of these products raw or recontaminated may result in illness. No major outbreaks of illness have been attributed to this organism.
Sporadic cases occur frequently, becoming more prevalent during the warmer months.
In a survey of cases of V. vulnificus infections in Florida from 1981 to 1987, Klontz et al. Raw oyster consumption was a common feature of primary septicemia and gastroenteritis, and liver disease was a feature of primary septicemia. Individuals with diabetes, cirrhosis, or leukemia, or those who take immunosuppressive drugs or steroids are particularly susceptible to primary septicemia. Methods used to isolate this organism from foods are similar to those used with diarrheic stools. To date, all food isolates of this organism have been pathogenic in animal models.