- An acute infectious disease caused by the gram-negative bacterium Vibrio cholerae
- Characterized by severe diarrhea with extreme fluid and electrolyte depletion, vomiting, muscle cramps, prostration, and potential death without fluid and electrolyte replacement (1)
- Endemic areas: India, Southeast Asia, Africa, Middle East, Southern Europe, Oceania, South and Central America (1)
- System(s) affected: gastrointestinal
- Synonym(s): Asiatic cholera; epidemic cholera; rice-water diarrhea; cholera gravis
Cholera in 3rd trimester of pregnancy is associated with greater dehydration and may lead to stillbirth. Significant dehydration is the greatest risk for poor fetal outcome.
- Vaccine is not recommended for children <6 months.
- Breastfeeding is protective.
- Predominant age: all ages
- Predominant sex: male = female
- 75% of patients infected with V. cholerae do not develop symptoms. Patients continue to shed the organism in their feces for 1 to 2 weeks after infection.
- 80% of clinical cases are mild to moderate; 20% are severe with high fatality rates if untreated.
- Most U.S. cases acquired through international travel
- El Tor (O1) is the predominant biotype and is responsible for the most recent epidemic (1).
- New serotype in Bangladesh, India (0139). Important because of lack of efficacy of standard vaccine; several new variants reported in Asia and Africa
- Usual course: acute, chronic, and relapsing
- In the early stages, severely affected patients can lose 1 L/hr of body fluids (1).
Etiology and Pathophysiology
- After ingesting an infectious dose (>108 organisms) through contaminated food/water sources, the organism reaches the small intestine where V. cholerae (O-group 1) produces an enterotoxin (CTX) that promotes fluid secretion into the intestinal lumen.
- Toxicity is mediated by A1 enterotoxin subunit, which increases cyclic adenosine monophosphate (cAMP) production. This results in a reduction of sodium and chloride absorption by intestinal microvilli and an increase in fluid excretion (massive watery diarrhea).
- The incubation period is 12 hours to 5 days, with a median of 1.5 days (1).
- Traveling or living in epidemic/endemic areas
- Exposure to contaminated food or water
- Person-to-person transmission (rare)
- In endemic areas, children <5 years of low socioeconomic status who do not breastfeed are at highest risk.
- Cases are more severe in patients with blood group O compared with AB (patients with blood types A, B, and AB have blood group antibodies in the mucosal layer which delays cholera toxin penetration of the small bowel ).
- Reduced gastric acid secretion: medications, gastrectomy
- Water purification
- Appropriate public sanitation
- Proper food selection and preparation (e.g., no unpeeled raw fruits or vegetables, no raw or undercooked seafood)
- Enteric precautions
- Chemoprophylaxis for exposed contacts is not routinely recommended (2,3)[C].
- Natural infection confers long-lasting immunity.
- Prophylactic vaccine
- The FDA-approved vaccine is for adults 18 to 64 years traveling to an area of active cholera transmission. It reduces severe diarrhea by 90% at 10 days and 80% at 90 days following vaccination. Safety in pregnant and breastfeeding women is unknown.
- Concomitant administration with yellow fever vaccine may decrease response to yellow fever.
Commonly Associated Conditions
Increased risk of disease with gastric achlorhydria
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