Vibrio

Vibrio is a genus of curved, motile, Gram-negative bacteria in the family Vibrionaceae. Members are predominantly aquatic, inhabiting marine and estuarine environments, and many species are halophilic or halotolerant, requiring salt for optimal growth. They are commonly found in warm coastal waters and can associate with plankton, shellfish, and other marine life.

In the laboratory, Vibrio species are oxidase-positive, facultatively anaerobic, and bacillary or curved rod-shaped. They are typically cultured on selective media such as thiosulfate-citrate-bile-salts-sucrose (TCBS) agar, where different species exhibit characteristic colony colors according to sugar fermentation. They are usually motile with a single polar flagellum and show growth over a range of temperatures, with many strains growing at human body temperature.

Several species have notable human health relevance. Vibrio cholerae, especially serogroups O1 and O139, causes epidemic and pandemic cholera, characterized by profuse watery diarrhea and dehydration. Vibrio vulnificus and Vibrio parahaemolyticus are marine pathogens linked to seafood-borne illness and wound infections; V. vulnificus can cause severe septicemia in individuals with liver disease or immunocompromise. Many other Vibrio species are dominantly environmental and only occasionally pathogenic.

Pathogenicity varies by species and includes toxins such as cholera toxin (ctxAB) and other virulence factors that promote adherence and tissue damage. Management of cholera relies on prompt fluid replacement and electrolyte management; other Vibrio infections may require antibiotics and wound care. Public health measures focus on safe seafood handling, proper cooking, and sanitation to limit outbreaks.