Question

How does Cholera affect and spread in the body?

Hint:

Cholera spreads via contaminated water and causes severe diarrhea by cholera toxin disrupting intestinal ion transport, leading to dehydration.

Answer 1

Transmission: Cholera spreads through the fecal-oral route, mainly by drinking water or consuming food contaminated with Vibrio cholerae bacteria. Contaminated water sources, poor sanitation, and improper hygiene practices are major contributors to the spread of cholera. Pathophysiology: After ingestion, the bacteria survive the acidic environment of the stomach and colonize the epithelial lining of the small intestine. They attach to the intestinal mucosa and release cholera toxin, which acts on the enterocytes (intestinal cells). The toxin activates adenylate cyclase enzyme in the intestinal cells, increasing cyclic AMP (cAMP) levels. This causes excessive secretion of chloride ions and water into the intestinal lumen while inhibiting sodium absorption. Clinical Effect: This massive loss of fluids and electrolytes results in the characteristic “rice water stools” — a watery, pale, and odorless diarrhea. The rapid fluid loss leads to dehydration, electrolyte imbalances (loss of potassium, sodium, bicarbonate), decreased blood volume, hypovolemic shock, and if untreated, death. Prevention: Prevention strategies include providing safe drinking water, improving sanitation and hygiene, proper sewage disposal, and health education. Vaccines against cholera are also available in endemic areas.