Page 101 - Journal of Special Operations Medicine - Summer 2014

An Ongoing Series

Cholera

Mark W. Burnett, MD

ABSTRACT
Vibrio cholerae is a comma-shaped, gram-negative rod Buffalo, NY, on 1 July. Cholera broke out among the
that produces an enterotoxin, which causes an acute-on- troops on 4 July. By 9 July, only 68 men of the seven
set diarrheal disease ranging in severity from mild to life companies that departed from Buffalo were left. Many
threatening. Worldwide, there are an estimated 3–5 mil- died of the disease on board ship; many others deserted
lion cases per year, with more than 100,000 deaths. The in panic and died of cholera in the surrounding country-
disease remains a significant cause of death and illness side” (see Mosley).
in sub-Saharan Africa, southeast Asia (especially Ban-
gladesh and India), and Haiti, and the infection should
be recognized by the Special Operations Forces (SOF) Clinical
medical provider. Humans become infected with V. cholerae by drink-
ing contaminated water containing the organism or by
Keywords: Vibrio cholerae, enterotoxin, diarrheal disease eating contaminated raw or undercooked shellfish har-
vested from brackish or saltwaters in endemic areas.
Approximately three-quarters of those infected with V.
cholerae remain asymptomatic but shed organisms back
Background
into the environment for up to 2 weeks, potentially in-
Vibrio cholerae is a comma-shaped, gram-negative rod fecting others. The number of the organisms ingested
that produces an enterotoxin, which causes an acute-on- determines the incubation time, which can be as short
set diarrheal disease ranging in severity from mild to life as 2 hours and as long as 5 days. Twenty percent of
threatening. Since the early years of the 19th century, those who become symptomatic develop profuse, life–
seven global cholera pandemics have resulted in millions threatening watery diarrhea without fever or abdominal
of deaths. The World Health Organization estimates cramping; the remainder of those who develop symp-
that yearly, between 3 and 5 million cases of cholera toms have a milder form of the disease.
and over 100,000 deaths occur worldwide. The dis-
ease has been nearly eliminated in the Developed World The progression of the disease in severe cases, known as
through the provision of clean water and proper sew- cholera gravis, can be striking. Voluminous watery stools
age treatment; however, it remains a significant cause of that are colorless with small amounts of mucus present
death and illness in sub-Saharan Africa, southeast Asia are characteristically described as “rice water” (Figure
(especially Bangladesh and India) and, in the Western 1) in appearance and can result in fluid losses of up to
Hemisphere, Haiti. Because cholera outbreaks can have 1L/hr. If left untreated, severe dehydration, metabolic
devastating consequences on the populations affected, acidosis, and electrolyte imbalances can rapidly develop
the infection should be recognized by the Special Opera- and lead to seizures, coma, and death. Typical features
tions Forces (SOF) medical provider. on examination include tachycardia, hypotension, de-
creased skin turgor, and dry mucous membranes. Lack
“One of the first experiences of American Soldiers with of prompt recognition and initiation of rehydration and
cholera fully demonstrates its devastating character and supportive care can be rapidly fatal, especially for those
shows how disastrous an outbreak can be to a mili- with HIV infection, those with blood group O, and chil-
tary operation. During the Black Hawk Indian War in dren in the first decade of life who are most susceptible
1832, seven companies of infantry troops destined for to the disease. Spread of the disease directly from person
this campaign embarked on the steamer Henry Clay at to person has been rarely documented.

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