Ch 21 Spirochetes, Vibrios from Table

Borrelia recurrentis vectors/hosts

Louse, ticks

Borrelia recurrentis causes

louse-borne relapsing fever, tick borne relapsing fever

Borrelia recurrentis virulence factors

Change surface antigens to evade the host's immune response.

Borrelia recurrentis treatment

Doxycycline, erythromycin

Leptospira interrogans transmission

Skin contact with water (or moist soil) contaminated by urine of infected animals (i.e. swine, badgers, rodents, deer, fox)

Leptospira interrogans causes

Leptospirosis, bacteremia

Leptospira interrogans treatment

IV Penicillin

Vibrio cholerae transmission

fecal-oral via contaminated water, uncooked shellfish

Vibrio cholerae symptoms

"rice water stools" due to mucus flecks in stools, Fluid loss
Blood becomes viscous (thick); pH drops, no fever, low abdominal pain

Vibrio cholerae virulence factor

cholera toxin

Cholera toxin mechanism

1. The cholera toxin AB5 binds a ganglioside.
2. AB5 toxin enters the cell by endocytosis.
3. The endosome travels to the endoplasmic reticulum.
4. A1 binds host G protein.
5. cAMP stimulates the chloride (Cl-) transporter CFTR.

Vibrio parahaemolyticus transmission

Ingestion of shellfish

Vibrio parahaemolyticus causes

gastroenteritis

Vibrio vulnificus transmission

Wound exposed to salt water, fecal-oral, contamined sea water

Vibrio vulnificus causes

Septicemia, Cellulitis after exposure of wounds to salt water

Vibrio vulnificus treatment

Doxycycline

Campylobacter jejuni transmission

fecal-oral via person-person, contaminated food, animal contact

Campylobacter jejuni lives in

Capneic (CO2), Microaerophilic environments

Campylobacter jejuni causes

gastroenteritis

Campylobacter jejuni virulence factors

Flagella enable the pathogen to burrow through mucus lining of the GI tract
Adheres to epithelial cells
Produces enterotoxins (cytotoxin) that causes host cell death.

Helicobacter pylori transmission

fecal-oral, water, fomites, cat feces

Helicobacter pylori causes

gastric ulcers and cancer

Helicobacter pylori treatment

Difficult to treat - require triple or quadruple therapy

Helicobacter pylori is urease

positive