Cholera is an illness caused by the bacterium Vibrio cholerae, which is contracted by eating contaminated food or drinking contaminated water. The bacteria can cause severe diarrhea * by producing a toxin that makes the intestines release more water and minerals than usual. The disease has a one- to five-day incubation period (the time between infection and when symptoms appear) and progresses very quickly. Most cases of cholera are mild, but in about one of 20 cases, the disease is serious. If left untreated, severe cholera can lead to death from dehydration * within hours. With treatment, the death rate is less than 1 percent.
In 1991, an epidemic * of cholera occurred in South America and some cases appeared in the United States shortly thereafter. Most cases of cholera reported in the United States can be traced to travel to an area where cholera is endemic * .
Haiti and the Dominican Republic had a major outbreak between October 2010 and January 2012. The outbreak started in Haiti in October 2010 and continued into the middle of 2015, with only temporary lulls. Scientists think the hurricane and weather conditions in Haiti worsened the outbreak, and the damaged sanitation systems allowed it to spread. By November 2010, the disease had spread into the neighboring country of the Dominican Republic. The epidemic sickened nearly 700,000 people and killed 9,069 in Haiti as of August 2015.
Cholera outbreaks in 2011 and 2012 in multiple African nations have led to intense campaigns for handwashing. In Sierra Leone, some 21,500 cases with 290 deaths were reported in 2012. Ghana had cholera epidemics in 2011 and 2012, with combined cases totaling 16,000 and 130 deaths. Ghana has been hit hard with outbreaks. In 2014 cholera hit the capital city Accra, with 11,000 cases and 100 deaths. The news stories of the outbreak of Ebola in nearby countries overshadowed this Ghana cholera outbreak.
Cholera is spread when people eat food or drink water that has been contaminated with feces * containing Vibrio cholerae. Risk factors for epidemics of cholera include unsanitary and crowded living conditions, war, famine (scarcity of food), and natural disasters that disrupt clean water delivery. For example, following a natural disaster such as a hurricane or flood, supplies of drinking water can become contaminated. The disease is most frequently spread in areas with poor sanitation and water treatment facilities.
During outbreaks of the disease, cholera may spread by contact with the feces of an infected person; Vibrio cholerae can live in feces for up to two weeks. It also spreads when people use contaminated water for cleaning or waste disposal. Eating raw or undercooked shellfish can be another way of contracting the disease because the bacteria can survive in slow-moving rivers and coastal waters. The few cases in the United States are typically caused by contaminated seafood from the Gulf of Mexico or seafood brought home by people who have traveled to other countries.
The major symptom of cholera is diarrhea, which can be severe and cause up to a quart of fluid loss per hour from the body. Diarrhea caused by cholera is painless, with stools that are fishy smelling and watery, often with flecks of mucus * in them (these are sometimes called “rice water” stools, because they look like rice floating in water).
Most cases of cholera are mild or moderate, and the disease can be difficult to distinguish from other ones that cause diarrhea. More serious cases can cause severe diarrhea, vomiting, and dehydration. Signs of dehydration include decreased urination, extreme tiredness, rapid heartbeat, dry skin, dry mouth and nose, thirstiness, and sunken eyes.
Because the symptoms of cholera are often identical to those of other illnesses that cause diarrhea, knowing that a person has traveled to a country where cholera is endemic is important in helping a doctor make the diagnosis. Blood and stool samples can be taken to look for evidence of the bacteria.
Treatment of cholera can be simple and effective, especially if it is given soon after symptoms appear. Rehydration, or replenishing the body with fluids, is the most important part of treatment. People can rehydrate effectively by drinking a mixture of sugar, salts, and clean water, known as an oral rehydration solution. The World Health Organization has an oral rehydration solution that is distributed worldwide through the efforts of the United Nations. In the United States, solutions can be bought or mixed at home. Such solutions replenish the fluid and salts lost by the body due to diarrhea and vomiting.
More serious cases of cholera may require intravenous (in-tra-VEEnus) fluids, or fluids injected directly into a vein. Antibiotics, which are given in severe cases, can shorten the time that the symptoms last and help prevent spread of the disease to others. However, widespread use of antibiotics for large populations is discouraged.
Complications from cholera are usually the result of severe dehydration. Seizures * , abnormal heart rhythms, shock * , damage to the kidneys * , coma * , and death can occur. Children, especially infants, are more likely to develop complications than adults because they are more prone to developing severe dehydration and body mineral imbalances.
Steps people can take to prevent contracting cholera when traveling or after a natural disaster include the following:
Vaccines * for cholera exist, but their effectiveness is short lived, and none are provided or recommended in the United States.
See also Bacterial Infections • Intestinal Infections
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Centers for Disease Control and Prevention. 1600 Clifton Rd., Atlanta, GA 30333. Toll-free: 800-311-3435. Website: http://www.cdc.gov (accessed November 28, 2015).
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* acute describes an infection or other illness that comes on suddenly and usually does not last very long.
* small intestine is the part of the intestines—the system of muscular tubes that food passes through during digestion—that directly receives the food when it passes through the stomach.
* diarrhea (di-ah-RE-a) refers to frequent, watery stools (bowel movements).
* dehydration (dee-hi-DRAY-shun) is a condition in which the body is depleted of water, usually caused by excessive and unreplaced loss of body fluids, such as through sweating, vomiting, or diarrhea.
* epidemic (eh-pih-DEH-mik) is an outbreak of disease, especially infectious disease, in which the number of cases suddenly becomes far greater than usual. Usually epidemics are outbreaks of diseases in specific regions, whereas widespread epidemics are called pandemics.
* endemic (en-DEH-mik) describes a disease or condition that is present in a population or geographic area at all times.
* feces (FEE-seez) is the excreted waste from the gastrointestinal tract.
* mucus (MYOO-kus) is a thick, slippery substance that lines the insides of many body parts.
* seizures (SEE-zhurs) are sudden bursts of disorganized electrical activity that interrupt the normal functioning of the brain, often leading to uncontrolled movements in the body and sometimes a temporary change in consciousness.
* shock is a serious condition in which blood pressure is very low and not enough blood flows to the body's organs and tissues. Untreated, shock may result in death.
* kidneys are the pair of organs that filter blood and remove waste products and excess water from the body in the form of urine.
* coma (KO-ma) is an unconscious state, like a very deep sleep. A person in a coma cannot be awakened, and cannot move, see, speak, or hear.