CHOLERA
Cholera is an acute diarrheal infection caused by the bacterium Vibrio cholerae. The most severe cases of cholera may lead to dehydration.
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Molecular causes of Cholera The symptoms are caused by a toxin that activates the membrane enzyme called adenylate cyclase. This enzyme converts adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP), which is a molecule involved in different regulatory processes in the cells, such as hormones activity, synaptic transmission in the nervous system and inflammatory and immune responses in the tissues. High cAMP levels increase the secretion of chloride ion and bicarbonate into the lumen. The ionic balance is disrupted causing water secretion into the intestinal lumen. |
In the acute phase of cholera, the loss of water from the small intestine is greater than the reabsorption in the large intestine, resulting in a major loss of fluids. Approximately, five percent of people infected with V. cholerae may present a severe cholera disease, which is characterized by profuse watery diarrhea, vomiting, and leg cramps. In these patients, the rapid loss of body fluids may lead to dehydration and prostration. The lack of proper and timely treatment can lead to death within hours.
A person can get cholera by eating food contaminated with the cholera bacterium. In an epidemic, the source of the contamination is usually the feces of an infected person.
