Taxonomy and Description of Vibrio fluvialis sp. nov. (Synonym Group F Vibrios, Group EF6)

Abstract

A numerical taxonomic study has been carried out to establish the relationship of group F to other biochemically similar organisms within the family Vibrionaceae. A total of 154 strains were examined including 59 of group F. Out of 114 characters determined for each strain 100 were used to compute average Euclidean distances between strains. Four methods of clustering were used, all of which gave very similar results. Strains resembling Vibrio anguillarum fell into clusters corresponding to V. anguillarum, Beneckea nereida and a previously unrecognized group, phenon 5. Strains of the Aeromonas hydrophila/punctata group formed a heterogenous phenon within which certain subdivisions, perhaps artificial, could be discerned. Group F strains all fell in one closely‐knit cluster distinct from all the species of Vibrio, Aeromonas, Plesiomonas and Photobacteriwn studied. Group F strains could be divided into two biovars, I and II. Both biovars are present in aquatic, particularly estuarine, environments throughout the world but biovar I strains have also been isolated from humans with diarrhoea. It is concluded that group F is a synonym of group EF6 and that the strains within these groups should be classified in a new species named Vibrio fluvialis. The type strain is NCTC 11327.

Cytotoxic and cell vacuolating activity of Vibrio fluvialis isolated from paediatric patients with diarrhoea

“…In this study, most of the V. fluvialis strains were isolated from children with diarrhoea, indicating that children may be the most vulnerable group to this pathogen. Retrospective studies conducted by the British Public Health Laboratories on lysine decarboxylase-negative Aeromonas strains showed that one-third of the strains were actually V. fluvialis (Lee et al, 1981). Thus, it is essential to include the salt tolerance test to differentiate these two species (Seidler et al, 1980;Lee et al, 1981), although there is a report on V. fluvialis strains capable of growing in absence of NaCl (Suthienkul et al, 1985).…”

“…These vibrios were designated 'group F' vibrios in England (Furniss et al, 1977) and 'CDC group EF6' in the USA (Huq et al, 1980). Taxonomic studies concluded that these organisms represented a new species, and they were designated as Vibrio fluvialis (Lee et al, 1981).…”

“…These vibrios were designated 'group F' vibrios in England (Furniss et al, 1977) and 'CDC group EF6' in the USA (Huq et al, 1980). Taxonomic studies concluded that these organisms represented a new species, and they were designated as Vibrio fluvialis (Lee et al, 1981).The distribution of V. fluvialis is worldwide (McNicol et al, 1980;Thekdi et al, 1982) and this organism is not only isolated from human diarrhoeal cases (Huq et al, 1980;Tacket et al, 1982;Thekdi et al, 1982;Hickman-Brenner et al, 1984;Klontz et al, 1994;Hodge et al, 1995) but also from marine and estuarine environments (Seidler et al, 1980;Lee et al, 1981;Morris & Black, 1985). There are reports of food poisoning caused by this organism (Kobayashi & Ohnaka, 1989;Thekdi et al, 1990), especially due to consumption of raw shellfish (Levine & Griffin, 1993).…”

“…Retrospective studies conducted by the British Public Health Laboratories on lysine decarboxylase-negative Aeromonas strains showed that one-third of the strains were actually V. fluvialis (Lee et al, 1981). Thus, it is essential to include the salt tolerance test to differentiate these two species (Seidler et al, 1980;Lee et al, 1981), although there is a report on V. fluvialis strains capable of growing in absence of NaCl (Suthienkul et al, 1985).All the V. fluvialis strains included in this study grew well in peptone water containing 7 % NaCl. Three strains were positive in the Voges-Proskauer test.…”

Numerical Taxonomy of Vibrios Isolated from Estuarine Environments

“…Lee et al (60,62) redescribed Vibrio metschnikovii and also named a new species, Vibriofluvialis (the group F vibrios; i.e., group EF6). The latter is considered to be intermediate between the genera Vibrio and Aeromonas (62). An organism capable of extensive tissue damage or death or both in humans was demonstrated by Clark and Steigerwalt (12) to be closely related to species of the genus Vibrio and was subsequently named Vibrio vufnificus by Farmer (28).…”