In October 2010, in the aftermath of the earthquake, cholera arrived in Haiti. The strain was likely brought into the country by well-meaning workers from Asia. Sadly, the setting was ripe for the rapid spread of this scourge. Within a year of the outbreak there were over a third of a million cases of cholera and 5,500 deaths! Within several years there were more than two thirds of a million cases and 8000 deaths. Cholera persists and the government has an ambitious program to eradicate the disease within a decade.
Cholera can kill within hours. Vibrio cholerae, the infecting bacteria, produces a toxin that interferes with salt and water transport in the duodenum and the upper jejunum, the first portions of the small intestine. The toxin activates adenylate cyclase, which increases cyclic adenosine monophosphate, which blocks sodium and chloride absorption, and promotes chloride and water secretion in the bowel. This results in profuse watery diarrhea that can rapidly lead to severe dehydration, shock, and death.
V cholerae is a saltwater organism that lives in association with plankton.
Cholera has 2 main reservoirs, humans and water. The bacteria is ingested in contaminated water or food. The bacteria is inactivated by acid in the stomach and infection depends on a large enough dose to circumvent the acid. Anything that reduces stomach acidity (antacids, histamine receptor blockers, proton pump inhibitors, H pylori infection) increases the risk for cholera.
Infection rates in household contacts range from 20 to 50%. Past infection results in antibodies to cholera and immunity to repeat infection.
Rapid rehydration with intravenous fluids is life saving.
Antibiotics are administered for moderate or severe infections. A single dose of tetracycline, doxycycline, or ciprofloxacin is effective to reduce the duration and volume of diarrhea. Single dose doxycycline is the preferred antibiotic. This antibiotic can cause permanent discoloration of the teeth if administered to children under the age of 8 years but the risk is small with a single dose.
Cholera can kill within hours. Vibrio cholerae, the infecting bacteria, produces a toxin that interferes with salt and water transport in the duodenum and the upper jejunum, the first portions of the small intestine. The toxin activates adenylate cyclase, which increases cyclic adenosine monophosphate, which blocks sodium and chloride absorption, and promotes chloride and water secretion in the bowel. This results in profuse watery diarrhea that can rapidly lead to severe dehydration, shock, and death.
V cholerae is a saltwater organism that lives in association with plankton.
Cholera has 2 main reservoirs, humans and water. The bacteria is ingested in contaminated water or food. The bacteria is inactivated by acid in the stomach and infection depends on a large enough dose to circumvent the acid. Anything that reduces stomach acidity (antacids, histamine receptor blockers, proton pump inhibitors, H pylori infection) increases the risk for cholera.
Infection rates in household contacts range from 20 to 50%. Past infection results in antibodies to cholera and immunity to repeat infection.
Rapid rehydration with intravenous fluids is life saving.
Antibiotics are administered for moderate or severe infections. A single dose of tetracycline, doxycycline, or ciprofloxacin is effective to reduce the duration and volume of diarrhea. Single dose doxycycline is the preferred antibiotic. This antibiotic can cause permanent discoloration of the teeth if administered to children under the age of 8 years but the risk is small with a single dose.
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