Advertisement
In short, cholera is an illness that results from infection by a bacterium called Vibrio cholerae. It produces a protein, called entero (for bowel)-toxin, which causes small intestine cells to lose fluid, sodium and potassium — sometime in immense amounts, up to as much as 20 liters (40 pints) a day. The bacteria rarely gets past the bowel and into the bloodstream to cause a general infection.
The severe form of cholera is a much-feared, familiar, centuries-old disease — particularly in its epidemic presentation. The natural habitat of V. cholerae is in coastal salt water and partial salty rivers, or estuaries that flow into the sea, such as the Nile or Ganges Deltas. It lives in close relation somehow to plankton.
Humans become infected incidentally from the water, but once infected, act as vehicles for spread. Ingestion of water contaminated by infested human feces is the most common route of acquisition. It also occasionally comes from food handled by a person with the bacteria on their hands. Let’s hear it for hand washing?
The incubation period is one to three days. The illness can be almost without symptoms (subclinical), a mild and uncomplicated “choleraic diarrhea,” or the classic picture, which involves the abrupt onset of massive liquid bowel movements, vomiting, some fever, belly pain and loss of fluid and cellular minerals.
Kidneys that try to conserve water can also quit working and fail. Shock and death can occur from the profound diarrhea — mostly in kids in areas of common infection and poor water.
Chronically infected adults develop some immunity to prevent symptoms, but they become carriers to re-contaminate the water used for all community activities.
The disease “runs” its course in two to seven days. Most people can get over cholera when adequate fluid is replaced soon enough. The 50 percent to 60 percent death rate often seen in epidemics can be reduced to near zero when proper fluids are replaced by mouth or intravenously.
The problem is availability and delivery of fluids to a disaster area. Additionally, uncontaminated drinking water is almost impossible to obtain, because clean water or means of sanitation (hygienic disposal of feces) are scarce.
Aside from such disasters, cholera is found most frequently in underdeveloped areas of the world, where people routinely excrete feces into the same water source used for bathing or drinking, such as a river.
When the bacteria spreads to previously uninvolved
territories, adults contract diarrhea as often as children, until they acquire some resistance to it. Antibiotics can’t help soon enough in the diarrhea, and the carrier state is difficult to eradicate.
So, as we sit in our sanitized studies on the porcelain recliner, reading about cholera elsewhere in the world, we must feel fortunate that we can put the news-paper or magazine aside and just flush and forget. Oh, don’t forget to wash your hands.
