Cholera, a bacterial disease spread through contaminated water that causes uncontrollable diarrhea and dehydration, can be fatal in just a few hours if not treated immediately. A cholera epidemic is difficult to control once it begins because several factors must be addressed simultaneously to stop the outbreak. A cholera epidemic begins with bacteria laden food or water which is ingested and excreted. Poor sanitation exposes others to the bacteria, and the cycle continues. Close quarters exacerbate epidemics and make prevention harder to achieve.
A cholera epidemic always starts with the presence of Vibrio cholerae, the bacteria that causes the disease. The bacteria may be found on unclean well walls and in seafood, raw fruit, vegetables, and grains. In a confined case of cholera, a person could ingest the bacteria and possibly contract the disease. The bacteria then would be flushed away in sewer systems. If working properly, the sewer systems keep excrement away from drinking water, and the cholera likely will not further harm others in the area.
An epidemic begins when an area suffers from a lack of proper sewers and sanitation. Feces with cholera bacteria will not be whisked away from the area’s water supply, but will instead come into contact with drinking water. Others unknowingly drink the water and are exposed to Vibrio cholerae. As they suffer from diarrhea, the bacteria-filled excrement again enters the water system and the cycle repeats.
This cycle is compounded when people live in extremely close quarters. Refugee camps, for example, are areas where people live in tight spaces with little to no sanitation. It is not unusual for a cholera epidemic to race through such settlements.
Failure to immediately treat cholera patients also is a primary factor in an epidemic. Without treatment, victims will experience ongoing and severe diarrhea. Every episode increases the risk that the cholera bacteria will return to public spaces, thus making others susceptible to the disease.
The aftermath of the 2010 Haiti earthquake is a classic case of these factors combining to create the conditions for a cholera outbreak. The devastating earthquake destroyed sanitation and sewer systems, and more than one million people were forced into tent cities after the quake destroyed entire towns. Cholera bacteria was introduced — its source unknown, but officials suspected it may have come from tainted food shipped into the country — and a cholera epidemic quickly emerged. Crowded conditions, dirty water, lack of sanitation, and minimal treatment combined to strike more than 100,000 people and caused several thousand deaths.