Vibrio mahadi ppt
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Transcript of Vibrio mahadi ppt
Vibrios
Sharq Elneil College
School of Medical Laboratory Sciences
Department of Microbiology
Medical Bacteriology course
U.Mahadi Hassan Mahmoud Bsc, Msc, MIBMS Microbiology
3 Important Genera:
Vibrio
Aeromonas,
Plesiomonas
Oxidase +ve
Medically important species
Vibrio cholerae
Vibrio paraheamolyticus
Vibrio vulnificus
Vibrio species Clinical Syndromes
–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
•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
Vibrio species Clinical Syndromes
Vibrio parahaemolyticus
•Seafood-associated
•Seen mostly in coastal regions
•Mild to moderate diarrhea
•Self-limiting disease, patients
recover uneventful
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.
50% mortality rate in
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.
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
Vibrio cholerae Gram-negative, curved rods
Vibrio cholerae Leifson flagella stain
Vibrio cholerae curved rods with polar flagellum (EM)
V. cholerae O1 ---------------------------------------------------
Biotye
El-tor Classic
Haemolysis (SRBC) + --
VP + --
Resistance to PB + --
---------------------------------------------------
VIRULENCE FACTORS:
oEnterotoxin: CT
oAdherence: Ability to Attach to the Microvilli at the Brush Borders of the Epithelial Cells.
EPIDEMIOLOGY:
oCauses Widespread Disease.
oHuman Carriers:
oModern International
PATHOGENESIS & CLINICAL INFECTION:
Infectious Dose:
Incubation period:
Abrupt Onset of Diarrhoea &
Vomiting
Stool > Watery (Rice Water),
Odorless
Fatality Rate:
LAB. DIAGNOSIS: Isolation & Identification of the Organism. Media: TCBS Transport Media:
TREATMENT: Prompt Replacement of Fluid & Elecrolytes Tetracycline and others
PREVENTION & CONTROL: Adequate Sewage Treatment and Water Purification Systems. Vaccination:
Typical Vibrio cholera contaminated water supply
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
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.