VIBRIO Flashcards
Comma-shaped or curved bacillus
vibrio
vibrio species
● V. cholerae
● V.parahaemolyticus
● V. alginolyticus
● V. metschnikovii
● V. damsel and
● V. hollisae
Facultatively anaerobic and monotrichous organisms
Facultatively anaerobic and monotrichous organisms
vibrio
vibrio found on
brackish water, marine water, or salt water
vibrio isolated from
algae, plankton, fish and shellfish
vibrio is halophilic except for
V. cholera and V.mimicus
vibrio Mode of acquisition:
raw or undercooked seafood.
vibrio related infection
Cholera
wound
infection
septicaemia
necrotizing
fasciitis
Vibrio
Microscopy
Gram negative, short, curved and asporogenous rods.
Common Isolate of Vibrio
● Vibrio cholerae O1 and non O1
● Vibrio parahaemolyticus
● Vibrio vulnificus
● Vibrio alginolyticus
colonies are smooth, opaque and iridescent with greenish hue
Vibrio on CAP
colonies are NLF (except: V.vulnificus, w/c is lactose fermenter)
Vibrion on MAC
colonies are Alpha or Beta hemolytic
Vibrio on BAP
Susceptibility test use in vibrio
150 ug vibriostatic O/129 disk in MHA
They are susceptible
all specie ferment
glucose
all specie except are non lactose fermenter
V. vulnificus
all specie are oxidase ____ and reduce _____ to nitrite except
V. metschnikovii
Motility test:
Broth
polar sheated flagella;
Motility test:
Solid media
peritrichous, unsheated flagella.
Causative agent of cholera
VIBRIO CHOLERAE
Rapid darting or shooting-star motility
VIBRIO CHOLERAE
Virulence factor of Vibrio Cholerae
Choleragen (cholera toxin)
Potent enterotoxins of Vibrio cholerae
Cholera toxin,zot toxin and ace toxin.
colonies are smooth and medium to large sized greenish hue
vibrio cholerae on CAP
Common cause of cholera
V. cholerae O1
Antigenic structure of Vibrio cholerae
Somatic O and
Flagellar H
● String test: Positive ● Other test:
● Oxidase: +
● Indole: +
● Lysine: +
● ODC: +
Vibrio cholerae
V. cholerae subgroups
V. choleraeO1
V. cholerae O139
V. cholerae non-O1
V. cholerae O1 serotypes
Ogawa (A, B),
Inaba (A, C) and
Hikojima (A, B, C)
Epidemic V. cholerae O1 biogroups:
Classical and El Tor
● Classical O1 biogroups- susceptible to polymyxin B, Voges Proskauer Negative
● El Tor biogroups- resistant to polymyxin B, Voges Proskauer Positive
● Acute diarrheal infection, spread through contaminated water source
● Ingestion of improperly preserved shellfish, milk and ice cream.
Cholera
Vibrio cholera
Hallmark: Rice watery stool
V. cholerae O1
Common cause of epidemic
Non-O1
Gastroenteritis
String Test: Rgt
0.5% sodium desoxycholate
Lysis of cells releases DNA, which can
then be pulled up into a viscous string
Positive reaction for String Test
VIBRIO CHOLERAE ON TSI
A/A
(-) Gas
(-)H2S
VIBRIO CHOLERAE ON LIA
K/K
(+) citrate & indole
Vibrio cholerae
(+) indole & cellobiose
V. vulnificus
(+) indole
V. mimicus
Second most common Vibrio species associated with gastroenteritis
Vibrio parahaemolyticus
Etiologic agent of “summer diarrhea” in Japan
Vibrio parahaemolyticus
MOA of vibrio parahaemolyticus
Eating contaminated seafood like oysters, scallops, crabs, lobsters, shrimps and sardines
Leading cause of pandemic
V. parahaemolyticus serotypes O3:K6
Virulence factor of Vibrio parahaemolyticus
Heat stable hemolysin
Pathogenicity of V parahaemolyticus
Hemolysin lysis human RBC’s
Selective medium for V parahaemolyticus
Wagatsuma agar (high mannitol medium
“Lactose positive” Vibrio species
Second to V. cholerae as cause
of severe Vibrio-associated
infections
Vibrio vulnificus
Related infections: Septicemia
and wound infection
MOA: Eating contaminated raw
oysters and fish
Vibrio vulnificus
Vibrio specie not commonly isolated and is considered as the least pathogenic to humans.
Strict halophile that requires a medium with 1% to 10% Nacl
Vibrio alginolyticus
Related infection: Eye, ear and wound infections (extraintestinal pathogen)
Vibrio alginolyticus
Alkaline peptone water, thiosulfate- citrate-bile salts-sucrose agar (TBCS), MAC and BAP
Culture Media used in Vibrio
Transport Medium in Vibrio
Cary-Blair medium
Enrichment medium for V. cholerae
Alkaline
peptone water (pH 8.5)
Growth of vibrios requires media that contain 0.5%
Nacl except
V. cholerae and V. mimicus
tolerates upto 10% NaCl
V. alginolyticus
grow as non-lactose fermenter
on MAC
Pathogenic vibrio
TCBS inhibit
Gram-positive bacteria
TCBS pH indicator
Thymol blue and parathymol blue
Sucrose fermenters (Yellow colonies on TCBS)
V.cholerae, V. alginolyticus and V. metschnikovii
Non-sucrose fermenter (Green colonies on TCBS)
V. mimicus, V. vulnificus, V. parahaemolyticus and V. damsel.
Used to separate vibrios (susceptible) from other oxidase-positive, glucose fermenter like aeromonads (resistant)
Uses 150ug vibriostatic agent O/129 (2,4-diamino- 6,7-diisopropylpteridine.).
VIBRIOSTATIC TEST – O/129
fail to agglutinate with O1 antisera
V. cholerae non-O1:
serotyped by O and K antigen.
V. parahaemolyticus:
150 ug vibriostatic O/129 disk orther name
2,4 diamino 6,7 diisopropylpteridine