TAXONOMY: cellular organisms -> Bacteria -> Proteobacteria -> Gammaproteobacteria -> Vibrionales -> Vibrionaceae -> Vibrio
Vibrio bacteria are gram-negative and largely halophilic. However, a few species are nonhalophilic, depending on their sodium chloride requirements. Most species are also oxidase-positive. Most species are sensitive to acid pH, but tolerant of alkaline pH. As pathogenic organisms, the CDC estimates that there are 8,000 infections and 60 deaths each year that are the result of Vibrio infections.Vibrio are often pathogens of humans. Several species of Vibrio, including V. cholerae, V. parahaemolyticus, and V. vulnificus, are known to cause seafood-borne illnesses such as septicaemia and wound infections. V. vulnificus is responsible for 95% of seafood-related deaths. While immunosuppressed individuals are most susceptible to Vibrio infections, these bacteria are capable of harming anyone. One of the symptoms of septicaemia is severe secondary lesions in the extremities. However, these cases are gender-specific, found routinely in males over 50. This is because estrogen protexted against the V. vulnificus endotoxin. Another major disease caused by Vibrio species is cholera, which occurs when V. cholerae colonizes the small intestine and releases enterotoxins. Many antibiotic medications are inneffective in treating cholera. Thanks to improved sewage and water treatment, there is a low occurrence of V. cholerae in the United States. Over 90% of the choerla cases occurring in the U.S. are the result of travel to a country where this bacterium is prevalent. Recurring infections of cholera are rare. Attempts at creating a cholera vaccine have had only limited success. Humans are the only natural host of V. cholerae.
This genus contains microbial species that can reside in the human gastrointestinal tract. [PMC 4262072]