1. Sharq Elneil College
School of Medical Laboratory Sciences
Department of Microbiology
Medical Bacteriology course
Vibrios
U.Mahadi Hassan Mahmoud
Bsc, Msc, MIBMS Microbiology

2. 3 Important Genera:
 Vibrio
 Aeromonas,
 Plesiomonas
Oxidase +ve

4. Medically important species
Vibrio cholerae
Vibrio paraheamolyticus
Vibrio vulnificus

5. Clinical Syndromesspecies
Vibrio
–Vibrio cholerae 01 (This is a
specific powerful serotype)
• Mild diarrhea to severe deadly
diarrhea
–Depends on how much toxin produced
• Vomiting can also occur
• Lose 10-25 liters a day, sometimes 1
liter/hour

6. • Lose 50% of body weight during
course of disease
• Death within hours (renal
failure and shock)
• Self-limiting, but have to replace
fluids and electrolytes or high
likelihood of eventual death
Vibrio cholerae non01 (less
potent serotype)
• Much milder diarrhea, not life-
threatening

7. Vibrio species
Clinical Syndromes
Vibrio parahaemolyticus
•Seafood-associated
•Seen mostly in coastal regions
•Mild to moderate diarrhea
•Self-limiting disease, patients
recover uneventful

8. Vibrio vulnificus
Diarrhea associated with raw
oysters
A more threatening infection is
when patients get a wound
infection contaminated with
seawater
The wound infection progresses
rapidly and can cause death within
a day.

9. Morphology
 Gram negative curved rod, measuring
3–4 0.5 μm
 Have a single flagellum at one end.
In smears made from solid cultures, the vibrios
may appear less The use of dilute carbon fuchsin
(1 in 10) is recommended as a counterstain in the
Gram technique
when staining Vibrio species.
 V. cholerae 0139, unlike V. cholerae 01, is
capsulated surrounded by a thick
capsule.

10. I. V. cholera O1:
– Agglutinate in Antisera Directed
Against O1 Antigen.
– Produce Enterotoxin.
2. Non-Toxigenic V. cholera O1:
3. Non O1 V. cholera (NCV, NAV):
II. V. cholerae O139

11. Vibrio cholerae
Gram-negative, curved rods

12. Vibrio cholerae
Leifson flagella stain

13. Vibrio cholerae
curved rods with polar flagellum (EM)

14. V. cholerae O1
---------------------------------------------------
Biotye
El-tor Classic
Haemolysis (SRBC) + --
VP + --
Resistance to PB + --
---------------------------------------------------

15. VIRULENCE FACTORS:
o Enterotoxin: CT
o Adherence: Ability to Attach to
the Microvilli at the Brush
Borders of the Epithelial Cells.
EPIDEMIOLOGY:
o Causes Widespread Disease.
o Human Carriers:
o Modern International

17. PATHOGENESIS & CLINICAL
INFECTION:
 Infectious Dose:
Incubation period:
Abrupt Onset of Diarrhoea &
Vomiting
Stool > Watery (Rice Water),
Odorless
Fatality Rate:

18. LAB. DIAGNOSIS:
Isolation & Identification of the
Organism.
Media: TCBS
Transport Media:

19. TREATMENT:
Prompt Replacement of Fluid &
Elecrolytes
Tetracycline and others

20. PREVENTION & CONTROL:
Adequate Sewage Treatment and
Water Purification Systems.
Vaccination:

21. Typical Vibrio cholera
contaminated water supply

23. Vibrio parahaemolyticus
oHalophilic vibrio
o Associated with seafood
o Gastroenteritis:
oOutbreaks of Food Poisoning
o Extraintestinal infections > wounds
oVirulence Factors:
oHaemolysin >
oheat-stable cytotoxin
oHeat-labile enterotoxin
oAdherence to human intestinal
cells

24. Aeromonas species
A. hydrophila, A. sobria & A.
caviae
Enterotoxins, Cytotoxins,
Haemolysins, Etc…
Gastroenteritis, Septicaemia, and
Skin & Wound Infections
Antimicrobial Suscebtibility
testing:
TMP-SMX, Tetracycline, Gentamicin
Resistant to b-Lactam Antibiotics.