the number of bacteria are typically higher. Under such 

 conditions, V. cholerae could conceivably multiply to a level 

 presenting a risk to divers. 



More recently, Colwell et al . (1981) isolated the more 

 virulent Vibrio cholerae serotype 01 from water samples of the 

 Chesapeake Bay and Louisiana salt marshes and sewers. The 01 

 strains demonstrated positive reactions for fluid accumulation 

 in rabbit ileal loops. Several strains also elicited positive 

 Y-l adrenal cell assays. In DNA probe analyses, an E. coli 

 labile toxin ( LT ) DNA probe lit up one of the 01 strains that 

 were tested, indicating the presence of the cholera toxin gene. 

 As with non-01 V. cholera , the 01 isolates were present in 

 samples collected from areas relatively free of fecal coliforms. 

 Therefore, levels of pollution as indicated by coliform counts do 

 not necessarily provide an accurate estimate of the safety of the 

 waters for either recreational or commercial diving. 



Vibrio vulnificus is another species of vibrio which may 

 pose a threat to divers. V. vulnificus has been isolated from 

 seawater, sediment, plankton, and animal samples collected from a 

 variety of locations from Miami, Florida to Cape Cod, 

 Massachusetts (Oliver et al., 1983). It is a ubiquitous 

 microorganism, occurring in widely different geographical areas 

 and has been isolated from a variety of environmental samples, 

 although in relatively low numbers. Of the V. vulnificus 

 isolates tested by Oliver et al. (1983), 82% were lethal for 

 mice upon injection. Although mice pathogenicity does not 

 necessarily imply human pathogenicity, the environmental isolates 

 of V. vulnificus should be considered potential human pathogens. 

 Oliver (1981) also noted that, in cases where V. vulnificus 

 infection was acquired through an open cut, the infections were 

 always associated with seawater. V. vulnificus can be remarkably 

 virulent, causing death if it infects a wound or is ingested. 

 Onset of infection is rapid, with symptoms occurring within 12-16 

 hours and death can occur within 24 hours. 



The organism causes extensive vascular tissue damage, 

 leading to a great amount of fluid accumulation. In cases of V. 

 vulnificus infection acquired by ingesting contaminated seafood, 

 the data indicate that elevated serum iron levels are required 

 to predispose an individual to the infection. In contrast, in 

 case studies where individuals acquired V. vulnificus infection 

 via wound contamination, the victims were relatively healthy to 

 begin with (Oliver, 1981). Thus, while the number of reported 

 cases of V. vulnificus infection is not high, the fatality rate 

 is rather high, and divers should be aware of the risk of such 

 infections if diving with an open wound. 



Seidler et al . (1980b) reported the isolation of a 

 bacterium resembling the genus Aerornonas , but requiring salt, 

 from the New York Bight. DNA hybridization experiments and G+C 



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