Vibrio Flashcards
The type of vibrio is
Gram-negative bacilli
Vibrio belong to the family…
Vibrionaceae
Vibrionaceae closely related to the family
Enterobacteriaceae
Vibrio associated with..
food-borne infections
The common species of vibrio is
Vibrio cholerae & Vibrio parahaemolyticus
Vibrio cholerae characterized by
Gram negative, curved rods (comma shape).
Non spore former & Motile (Polar flagella- darting motility)
Facultative anaerobes , grow in alkaline condition (> pH 8.0).
Oxidase +
Ferment carbohydrates+
Sensitive to
Heat , acid and drying
How much serotype of V. cholerae ?
139 according to their O antigen
Cholera is one of the
serious gastrointestinal disease.
How they transmit.?
Contaminated raw and undercooked seafood (infection dose 103). Contaminated water through drinking, cooking, washing, or
swimming (infection dose 109).
What is the Main Virulence factors:
Pilli: adherence to mucosal cells
Flagella: chemotaxis and moving to the intestinal mucosal
membrane.
Potent Cholera toxin (enterotoxin or exotoxin).
What is culture of V. cholerae
❑ Culture:
- Enrichment media: alkaline peptone water (pH 8.5)
- Selective & differential media: Thiosulphat-Citrate-Bile
salts Sucrose agar (TCBS).
- Incubation aerobically, 35°C.
Identification test
1 Biochemical identification:
- Gram stain: Gram negative comma shaped
bacilli.
- Oxidase test: (+ve) Positive
- API 20E
2- Serology: slide agglutination using specific
antisera to detect V. cholerae O antigen
3- Antibiotic sensitivity testing (AST).
What is the treatment?
1- Use Antibiotic is not necessary unless it’s used to decrease the infection duration. 2-Use interventions of salt solution. 3-Oral rehydration solution (ORS) : solution of electrolytes and glucose.
How we can prevent the infection.?
improving sanitation and use clean water and food supply .
▪ New oral cholera vaccine (Dukoral) offer >50% protection and lasts for 2yrs
▪ Vaccines are not useful in Epidemic control
