Cholera is a bacterial disease usually spread through contaminated water. Cholera causes severe diarrhea and dehydration. Left untreated, cholera can be fatal within hours, even in previously healthy people.
Modern sewage and water treatment have virtually eliminated cholera in industrialized countries. But cholera still exists in Africa, Southeast Asia and Haiti. The risk of a cholera epidemic is highest when poverty, war or natural disasters force people to live in crowded conditions without adequate sanitation.
Cholera is easily treated. Death from severe dehydration can be prevented with a simple and inexpensive rehydration solution.
Most people exposed to the cholera bacterium (Vibrio cholerae) don't become ill and don't know they've been infected. But because they shed cholera bacteria in their stool for seven to 14 days, they can still infect others through contaminated water.
Most cases of cholera that cause symptoms cause mild or moderate diarrhea that's often hard to tell apart from diarrhea caused by other problems. Others develop more-serious signs and symptoms of cholera, usually within a few days of infection.
Symptoms of cholera infection can include:
Dehydration. Dehydration can develop within hours after cholera symptoms start and range from mild to severe. A loss of 10% or more of body weight indicates severe dehydration.
Signs and symptoms of cholera dehydration include irritability, fatigue, sunken eyes, a dry mouth, extreme thirst, dry and shriveled skin that's slow to bounce back when pinched into a fold, little or no urinating, low blood pressure, and an irregular heartbeat.
Dehydration can lead to a rapid loss of minerals in your blood that maintain the balance of fluids in your body. This is called an electrolyte imbalance.
An electrolyte imbalance can lead to serious signs and symptoms such as:
The risk of cholera is slight in industrialized nations. Even in areas where it exists you're not likely to become infected if you follow food safety recommendations. Still, cases of cholera occur throughout the world. If you develop severe diarrhea after visiting an area with active cholera, see your doctor.
If you have diarrhea, especially severe diarrhea, and think you might have been exposed to cholera, seek treatment right away. Severe dehydration is a medical emergency that requires immediate care.
A bacterium called Vibrio cholerae causes cholera infection. The deadly effects of the disease are the result of a toxin the bacteria produces in the small intestine. The toxin causes the body to secrete enormous amounts of water, leading to diarrhea and a rapid loss of fluids and salts (electrolytes).
Cholera bacteria might not cause illness in all people who are exposed to them, but they still pass the bacteria in their stool, which can contaminate food and water supplies.
Contaminated water supplies are the main source of cholera infection. The bacterium can be found in:
Everyone is susceptible to cholera, with the exception of infants who get immunity from nursing mothers who have previously had cholera. Still, certain factors can make you more vulnerable to the disease or more likely to have severe signs and symptoms.
Risk factors for cholera include:
Cholera can quickly become fatal. In the most severe cases, the rapid loss of large amounts of fluids and electrolytes can lead to death within hours. In less extreme situations, people who don't receive treatment can die of dehydration and shock hours to days after cholera symptoms first appear.
Although shock and severe dehydration are the worst complications of cholera, other problems can occur, such as:
Cholera is rare in the United States with the few cases related to travel outside the U.S. or to contaminated and improperly cooked seafood from the Gulf Coast waters.
If you're traveling to areas known to have cholera, your risk of contracting the disease is extremely low if you follow these precautions:
Drink only safe water, including bottled water or water you've boiled or disinfected yourself. Use bottled water even to brush your teeth.
Hot beverages are generally safe, as are canned or bottled drinks, but wipe the outside before you open them. Don't add ice to your drinks unless you made it yourself using safe water.
For adults traveling from the United States to areas affected by cholera, a vaccine called Vaxchora is available in the United States. It is a liquid dose taken by mouth at least 10 days before travel.
A few other countries offer oral vaccines as well. Contact your doctor or local office of public health for more information about these vaccines. Even with the vaccine, it's important to take the above precautions to prevent cholera.
Although signs and symptoms of severe cholera can be unmistakable in areas where it's common, the only way to confirm a diagnosis is to identify the bacteria in a stool sample.
Rapid cholera dipstick tests enable doctors in remote areas to quickly confirm a cholera diagnosis. Quick confirmation helps to decrease death rates at the start of cholera outbreaks and leads to earlier public health interventions for outbreak control.
Cholera requires immediate treatment because the disease can cause death within hours.
Rehydration. The goal is to replace lost fluids and electrolytes using a simple rehydration solution, oral rehydration salts (ORS). The ORS solution is available as a powder that can be made with boiled or bottled water.
Without rehydration, approximately half the people with cholera die. With treatment, fatalities drop to less than 1%.
Seek immediate medical care if you develop severe diarrhea or vomiting and are in or have very recently returned from a country where cholera occurs.
If you believe you've been exposed to cholera, but your symptoms are not severe, call your family doctor. Be sure to say that you suspect your illness may be cholera.
Here's some information to help you get ready for your appointment.
When you make your appointment, ask if there are restrictions you need to follow before your visit.
Make a list of:
Some questions to ask your doctor about cholera include:
Your doctor is likely to ask questions, such as:
Stay well hydrated. For diarrhea and vomiting that may be cholera-related, use an oral rehydration solution.
In most developing countries, you can buy powdered packets of oral rehydration salts (ORS) originally developed by the World Health Organization to treat diarrhea and dehydration in infants with cholera. Stir the powder into clean drinking or boiled water according to the package directions.
If no oral rehydration solutions are available, make your own by combining 1 quart (about 1 liter) of bottled or boiled water with 6 level teaspoons (about 30 milliliters) of table sugar and 1/2 level teaspoon (about 2.5 milliliters) of table salt.
© 1998-2021 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved.