Vibrio vulnificus

Primary Statistics
  • Gram negative
  • Motile
  • Bacterium
  • Slightly curved

This bacterium has only been recognised fairly recently, and comes from the Vibrionaceae family, alongside Vibrio cholerae, Vibrio fischeri and Vibrio parahaemolyticus. Vibrio refers to the shape of the bacterium, as it is in a curved shape compared to the regular straight rod Bacilli. It is mainly found in marine environments, primarily in the coastlines surrounding the Atlantic, although it has recently been found in virulent strains off the coast of Mexico. and was first recognised at a pathogenic agent in 1976. The primary pathogenic function of this bacterium is the causation of, in cases of ingestion, severe vomiting and diarrhoea, accompanied by by muscular pains in the area surrounding the intestines. It also causes septicaemia when exposed to an open wound in human tissue or when ingested by an individual with a highly compromised immune system. It has been shown that V. vulnificus is susceptible to high salinity environs (at levels above 30 parts per trillion). However, it is still classified as a halophilic bacterium, depending on the source material read. This could lead to it being classified as halotolerant, simply due to the arguments for both sides being backed up by evidence from live samples.


Reports show that although recorded cases of infection by V. vulnificus are rare, it is believed this is influenced by both underreporting and misrepresented by other bacterium as being the causative agent. This can occassionally lead to fatal mistakes in diagnosis and treatment. The only group to whom V. vulnificus represents a serious heath risk are the immunocompromised, particularly those with liver infections, diabetes and similar health problems, in whom the bacterium causes primary septicaemia which spreads throughout the bloodstream and instigates septic shock. In these cases, the rate of fatality can jump alarmingly.

Risk assessment of Vibrio vulnificus in raw oysters: interpretative summary and technical reportVolume 8 of Microbiological risk assessment series, World Health Organisation, Food and Agriculture Org., 2005, p24
Totora, G et al; Microbiology: An Introduction; Pearson, 2010, p717