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Vibrios, Helicobacter &

Campylobacters

Junqi Zhang (张俊琪), PhD

MOH&MOE Key Lab of Medical Molecular Virology

Shanghai Medical College, Fudan University

(复旦大学上海医学院分子病毒学教育部/卫生部重点实验室)

Vibrios, Helicobacter &

Campylobacters

10/14/2013 Vibrios, Helicobacter &

Campylobacters/ Junqi Zhang

3

General Introduction

Vibrio cholerae produces an enterotoxin that

causes cholera, a profuse watery diarrhea that

can rapidly lead to dehydration and death

Helicobacter pylori has been associated with

gastritis and duodenal ulcer disease

Campylobacter jejuni is a common cause of

enteritis in humans



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Vibrio cholerae

free-living inhabitant of fresh water, but

causes infection only in humans

Electronic microscope Gram’s stain



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The Medically Important Vibrios

Organism Human Disease

V.cholerae serogroups O1 and O139 Epidemic and pandemic cholera

V.cholerae serogroups non-O1/non-

O139

Cholera-like diarrhea; mild diarrhea;

rarely, extra intestinal infection

V.parahaemolyticus Gastroenteritis, perhaps extra

intestinal infection

Others

V.mimicus, V.vulnificus, V.hollisae,

V.fluvialis, V.damsela, V.anginolyticus,

V.metschnikovii

Ear, wound, soft tissue, and other

extraintestinal infections, all

uncommon



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Genus Vibrio

V.cholerae

Other species

Serotype O1

Non-O1 -other serovars

biotypes

Serosubgroups

Phage types

E1 Tor

classical

OgawaInaba

Hikojima

V. parahaemolyticus: food-associated diarrheal disease

V. vulnificus: wound infection; septicemia

V.alginolyticus: otitis externa; wound infection

Non-agglutinating vibrios

Non-cholerae vibrios



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Antigenic Structure & Biologic Classification

a single heat-labile flagellar H antigen

O lipopolysaccharides (confer serologic specificity )

classic biotypes

El Tor biotypes

produces a hemolysin

resistant to polymyxin B

Antigenic Structure

Biologic Classification(O1)



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Gram-negative

Comma shape or curved rod

actively motile by means of a

polar flagellum

Morphology & Identification



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Growth Characteristics

ferments sucrose and mannose but not arabinose

Halophilic( requiring the presence of NaCl to grow )

Culture

convex, smooth, round colonies that are opaque and

granular in transmitted light

V.cholerae grows well one (TCBS) agar

vibrios grow at a very high pH (8.5–9.5) and are

rapidly killed by acid



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(TCBS) agar pH (8.5–9.5)

Negative

control



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Vibrio cholerae Enterotoxin

V.cholerae produce a heat-labile enterotoxin

consisting of 5 subunits B and 1 subunit A

Mechanism similar to Heat

labile toxin of ETEC

Diarrhea occurs—as much as 20–30

L/d—with resulting dehydration,

shock, acidosis, and death

Adenyl cyclase activated

cyclic AMP

secretion water/ions

subunit A

Vibrio choleraeEnterotoxin

1 2

3 4

hypersecretion of

electrolytes and water

Dehydration

shock

acidosis

death

10/14/2013 12Vibrios, Helicobacter &



Campylobacters/ Junqi Zhang13

“rice water” stool



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Pathogenisis of Cholera toxin

Do not reach the bloodstream but

remain within the intestinal tract

Virulent V.cholerae organisms

attach to the microvilli of the brush

border of epithelial cells

Multiply and liberate cholera toxin

and perhaps mucinases and

endotoxin

Infective dose vary dependent on

host gastric acidity

Pathogenesis &

Pathology

Clinical Findings

incubation period : 1–4 days

sudden onset of nausea and vomiting

and profuse water diarrhea with

abdominal cramps

rice water stool: contain mucus,

epithelial cells, and large numbers of

vibrios





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Diagnostic Laboratory Tests

Specimens stools contains mucus flecks for culture

Smears

motile vibrios

Culture

Enrichment culture: peptone agar, on blood agar with a pH near 9.0

Selection: on TCBS agar

Specific Tests

identified by slide agglutination tests using anti-O group 1 or

group 139 antisera



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Treatment

water and electrolyte replacement

antimicrobial agents

Many antimicrobial agents are effective

against V cholerae (Oral tetracycline )



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Prevention & Control

spread by water, food, and flies

Vibrio cholerae lives attached to algae, copepods, and

crustacean shells

Rest on education and on improvement of sanitation,

particularly of food and water

Patients should be isolated, their excreta disinfected,

and contacts followed up

Control

Prevention



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Epidemiology

Seventh pandemics (worldwide epidemics) of

cholera occurred between 1817 to date

Six pandemics (worldwide epidemics) of cholera

occurred between 1817 and 1923, caused most likely by

V cholerae O1 of the classic biotype and largely

originating in Asia, usually the Indian subcontinent.

The seventh pandemic began in 1961 in the Celebes

Islands, Indonesia, with spread to Asia, the Middle

East, and Africa. This pandemic has been caused by V

cholerae biotype El Tor 19

The Ganges River in India is

considered sacred, and people

wash in the river and drink from it.



However, cholera bacilli frequently inhabit the river and pass easily

among unsuspecting bathers.





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Questions

What are the virulent determinants of V.cholera,

clarify its pathogenesis



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Vibrio parahaemolyticus

V.parahaemolyticus is a halophilic bacterium that causes acute

gastroenteritis following ingestion of contaminated seafood such as

raw fish or shellfish

The enteritis induced

by V.parahaemolyticus

occurs worldwide, with

highest incidence in

areas where people eat

raw seafood

restoration of water

and electrolyte balance

Helicobacter pylori

Helicobacter pylori is a spiral-shaped gram-negative rod

H.pylori is associated with antral gastritis, duodenal (peptic) ulcer disease,

gastric ulcers, and gastric carcinoma, MALT lympomas



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In 2005, the Karolinska Institute in Stockholm awarded the Nobel Prize in

Physiology or Medicine to Marshall and Robin Warren, his long-time collaborator,

"for their discovery of the bacterium Helicobacter pylori and its role in gastritis and

peptic ulcer disease"

http://en.wikipedia.org/wiki/Karolinska_Institutet

http://en.wikipedia.org/wiki/Nobel_Prize_in_Physiology_or_Medicine

http://en.wikipedia.org/wiki/Gastritis



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Culture

H pylori grows in 3–6 days when incubated at 37 °C in a

microaerophilic environment

Growth Characteristics

oxidase-positive

catalase-positive

mobile

strong producer of urease

The Cag pathogenicity island

is usually absent from H.

pylori strains isolated from

humans who are carriers of H.

pylori, but remain

asymptomatic.

http://en.wikipedia.org/wiki/File:Regions_of_stomach.svg

http://en.wikipedia.org/wiki/File:Regions_of_stomach.svg



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Pathogenesis

The bacteria invade the epithelial cell surface to a limited degree

Toxins and lipopolysaccharide may damage the mucosal cells

ammonia produced by the urease activity may directly damage

the cells also

Pathology

chronic and active inflammation

Polymorphonuclear and mononuclear cell infiltrates



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Clinical Findings

upper gastrointestinal illness with nausea and pain;

vomiting and fever

the H.pylori infection persists for years and perhaps

decades or even a lifetime

About 90% of patients with duodenal ulcers and 50–80%

of those with gastric ulcers have H.pylori infection

have a role in gastric carcinoma and lymphoma



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Specimens

Smears

Special TestsRapid tests to detect urease activity are widely used for

presumptive identification of H pylori in specimens （ 13C urea

breath test）

Gastric biopsy specimens

gastroscopy procedure with biopsy is required



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Treatment

Triple therapy

with metronidazole

either bismuth subsalicylate or bismuth subcitrate

either amoxicillin or tetracycline for 14 days

Proton pump inhibitors directly inhibit H.pyloriand appear to be potent urease inhibitors



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Epidemiology & Control

H pylori is present on the gastric mucosa of less than 20%

of persons under age 30 but increases in prevalence to 40–

60% of persons age 60, including persons who are

asymptomatic

In developing countries, the prevalence of infection may be

80% or higher in adults

Person-to-person transmission of H pylori is likely

because intrafamilial clustering of infection occurs

33



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Questions

1. Which diseases can be caused by Hp？

2. What are the culture condition for Hp？

3. What are therapy for eradication of Hp in

patient?



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Key words

Cholerae

Vibrio cholerae enterotoxin

Vibrio cholerae O1,O139 & El Tor biotypes (Serotype)

TCBS agar , Halophilic

Helicobacter pylori, duodenal (peptic) ulcer , gatric ulcer,

gastric carcinoma

Vibrio parahaemolyticus

Thank you!



37

Campylobactercause both diarrheal and systemic diseases

Campylobacter jejuni & Campylobacter coli

causing mainly enteritis and occasionally systemic infection



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Morphology & Identification

gram-negative rods with comma shape

motile, with a single polar flagellum

do not form spores

Culture

Incubation of primary plates for isolation of C

jejuni should be at 42 °C to prevent growth of

most of the other bacteria



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Antigenic Structure & Toxins

lipopolysaccharides with endotoxic activity

Cytopathic extracellular toxins and enterotoxins

Pathogenesis & Pathology

acquired by the oral route from food, drink, or contact

with infected animals or animal products

multiply in the small intestine, invade the epithelium,

and produce inflammation that results in the

appearance of red and white blood cells in the stools

Localized tissue invasion coupled with the toxic activity

appears to be responsible for the enteritis



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Clinical Findings

acute onset of cramp abdominal pain, profuse

diarrhea that may be grossly bloody, headache,

malaise, and fever


Specimens Diarrheal stool

Smears Gram-stained smears of stool may show the

typical "gull wing"-shaped rods

Culture Culture on the selective media

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