Cholera is a bacterial infection of the intestines that causes severe diarrhea. It is generally spread when feces infected with the cholera bacterium contaminates a water supply, meaning areas with poor sanitation and untreated water are at high risk of cholera. In addition, natural disasters that crowd a large group of people together can result in a cholera epidemic. The incubation period, or time from exposure to appearance of symptoms, is between a few hours to a few days. This means a large population exposed to cholera will start to show symptoms at nearly the exact same time.
If untreated, cholera can cause a rapid loss of fluids leading to dehydration and, within a few hours, death. While it is rare in areas where treated water is prevalent, cholera is responsible for up to 120,000 deaths worldwide per year.
How is Cholera Contracted?
Cholera is transmitted through contaminated water. A bacterium known as Vibrio cholerae is found in the coastal waters of the Gulf Coast, Pacific Ocean, and Atlantic Ocean. It is also present in brackish water, which are areas where fresh water and salt water mix. The bacteria can attach to certain types of shellfish or raw fruits and vegetables. People who drink the water or eat contaminated shellfish can become infected and, even if they do not become sick, can release the bacteria in their stool. In areas with poor sanitation, the waste may come in contact with drinking water and be consumed by others.
Cholera is rarely transmitted through person-to-person contact, because the amount of bacteria necessary for infection is very large; over a million cholera bacteria are needed to infect a single person.
This large amount of bacteria can overwhelm a person’s stomach acid and travel to their small intestine. The bacteria then release a toxin that forces the small intestine to secrete water which is expelled as diarrhea. As a cholera patient loses fluids through diarrhea, they quickly become dehydrated.
Cholera is most common in places with any of the following conditions:
Poor water sanitation
Poor waste sanitation
Areas heavily affected by war
Natural disasters that isolate a large group of people together
Almost three fourths of the population infected with cholera shows no symptoms. These people are considered carriers who can potentially spread the illness for up to two weeks after contracting the disease.
Around 80 percent of those who exhibit symptoms experience only mild diarrhea and vomiting. However, the remaining 20 percent have symptoms that are severe and potentially deadly.
Signs of cholera generally start within five days of being exposed to the bacteria. Once symptoms start, they are fast acting. A trademark of cholera is watery diarrhea that is a gray color with visible mucus resembling flecks of rice.
Someone suffering from cholera can become dehydrated within hours, which leads to abdominal cramps, dry mouth and skin, and sunken eyes. Dehydration creates an absence of water and salt in the body. If a person remains dehydrated for too long, their kidneys can shut down, they can go into hypovolemic shock or a coma, and eventually die.
Losing too much fluid through diarrhea and vomiting, can cause someone to go into hypovolemic shock. This is one of the most dangerous progressions associated with cholera. The heart cannot pump enough blood to the body and eventually the organs shut down.
In areas where an outbreak of cholera has occurred, sometimes a doctor can diagnosis the disease on symptoms alone.
Otherwise, clinical confirmation of the disease needs to be done through a fecal culture or rectal swab. A stool sample is taken to a lab where it is placed in a gel that activates the growth of microorganisms. If the sample grows, infection is confirmed. There are also rapid dipstick tests in areas where epidemics are a possibility. These give a quicker determination and aid in early treatment.
The goal of treatment is to re-hydrate as quickly as possible. Cholera can kill in a matter of hours; however, if treatment is administered on time, results are extremely positive. Timely treatment of cholera can reduce the chances of death to less than one percent.
There are several methods of re-hydration available:
Oral Rehydration Salts (ORS): the World Health Organization created a solution of sugar and electrolytes that is mixed with clean water. It is a cheap, commonly used solution that re-hydrates 80 percent of those who use it.
Intravenous fluid: for advanced cases of cholera, intravenous fluids are used for fast hydration.
Antibiotics: although these do not stop the cholera bacteria from releasing toxins, antibiotics can help lessen diarrhea and vomiting and slow the loss of fluids.
Make sure water is safe. All cooking, cleaning, and drinking should be done from unopened bottles of water, water that has been boiled, or water treated with chlorine.
Basic hygiene. Washing hands before eating and after using the restroom is one of the best methods of prevention for cholera. When bathing outdoors, do so at least 30 meters from water sources used for drinking.
Avoid undercooked food. Do not eat raw seafood and make sure all food is cooked and hot. Room temperature food can hold the cholera bacteria for several days. The bacteria are also resistant to freezing. In addition, be careful of fruits that may have been washed with contaminated water.
Cholera remains a leading cause of death in the world. It can be deadly if contracted, but is easily treatable. If you are exposed to the bacteria and experience moderate to severe symptoms, do not try and wait it out. Seek help and hydration immediately.