Vibrio

• What is the order that includes the family Vibrionaceae?

  Order Vibrionales
• What is the type genus of the family Vibrionaceae?


  Vibrio
• What are the general morphological characteristics of Vibrionaceae?

  They are Gram negative straight/curved rods.
• What is the oxygen requirement for Vibrionaceae?

  They are facultative anaerobes.
• What biochemical test result is positive for most members of Vibrionaceae?

  Oxidase positive
• What is the G+C content of Vibrionaceae?

  47%
• What is the optimum growth temperature for Vibrionaceae?

  30-35 ˚C
• How many chromosomes do members of Vibrionaceae typically have?

  Two chromosomes
• What is a key requirement for the growth of Vibrionaceae?

  Requirement for NaCl (salt)
• What is the motility characteristic of Vibrionaceae?

  They are motile with a single polar flagella.
• What is the habitat preference for Vibrionaceae?

  They thrive in marine and brackish water.
• Which genera are included in the order Vibrionales?


  Vibrio
• What is the main clinical symptom of V. parahaemolyticus infection?

  Watery diarrhoea
• What is the typical outcome of a V. parahaemolyticus infection?

  It is typically a self-limiting illness.
• What are the symptoms of soft tissue infections caused by V. parahaemolyticus?

  Symptoms include swelling, pain, erythema, and necrosis.
• What is the primary route of infection for V. vulnificus?

  Exposure to seawater or raw oysters.
• What are the key virulence factors of V. vulnificus?

  Hemolysin, proteases, and capsule.
• What is the infectious dose for V. cholerae?

  It varies, but can be very low.
• What is the role of cholera toxin (CT) in V. cholerae infection?

  It induces secretory diarrhoea.

  
• What are the steps during V. cholerae infection?

  1. Ingestion and passage through acidic stomach
  2. Colonisation of small intestine
  3. Production of cholera toxin (CT)
  4. Exit from host in mucus-associated aggregates

  
• What are the differences between Vibrionaceae and Enterobacteriaceae?

  • Vibrionaceae have 2 chromosomes, while Enterobacteriaceae have 1.
  • Vibrionaceae are mostly oxidase positive.
  • Vibrionaceae primarily inhabit aquatic environments.
• What are the main pathogenic Vibrio species and their associated diseases?

  • V. cholerae: cholera
  • V. parahaemolyticus: shellfish-borne infections
  • V. vulnificus: wound infections and foodborne illnesses
• What are the clinical features of cholera caused by V. cholerae?

  • Short incubation period (< 12 hours)
  • Painless watery diarrhea (up to 1L/hour)
  • Severe dehydration and hypovolemic shock
• What are the virulence mechanisms of V. parahaemolyticus?

  • Hemolysins (e.g., TDH)
  • Type 3 secretion system (T3SS)
• What is the impact of V. cholerae O1 on public health?

  • Endemic to 50 countries
  • Affects 3-5 million individuals annually
  • Considerable social and economic burden
• What are the symptoms of V. vulnificus infections?

  • Wound infections: swelling, pain, necrosis
  • Foodborne illnesses: fever, hypotension, shock