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What is cholera? 
Cholera is a bacterial illness that can cause severe diarrhea and dehydration in people. 
How does a person get cholera? 
A person can get cholera by drinking water or eating food contaminated with the cholera 
bacterium. Water may be contaminated by the feces of an infected person or by untreated 
sewage. Food is often contaminated by water containing cholera bacteria or because it was handled by a person ill with cholera. In an epidemic, the disease can spread rapidly in areas with inadequate treatment of sewage and drinking water. The disease is not likely to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill. 
What are the symptoms of cholera? 
Often people with cholera have no symptoms or mild symptoms, but sometimes the illness can be severe. Symptoms include watery diarrhea, vomiting, and leg cramps. This can cause rapid loss of body fluids which leads to dehydration and shock. 
How long after infection do the symptoms appear? 
It can take anywhere from a few hours to 5 days for symptoms to appear after exposure. Symptoms usually appear in 2-3 days. ​
What should I do if I think I have cholera? 
If you think you may have cholera, seek medical attention immediately. Dehydration can be rapid so fluid replacement is essential. 
How is cholera diagnosed? 
To test for cholera, doctors must take a stool sample and send it to a laboratory to look for the cholera bacterium. 
What is the treatment for cholera? 
Cholera can be simply and successfully treated by immediate replacement of the fluid and salts lost through diarrhea. Patients can be treated with oral rehydration solution, a prepackaged mixture of sugar and salts to be mixed with water and drunk in large amounts. This solution is used throughout the world to treat diarrhea. Severe cases also require intravenous fluid replacement. Antibiotics can shorten the course and lessen the severity of the illness but they are not as important as receiving rehydration. 

How can I avoid getting cholera? 
Cholera is very rare in the United States; however, the illness still occurs in other parts of the world, including India and sub-Saharan Africa. Recently people have become ill with cholera after traveling to or living in some areas of the Caribbean (such as Haiti or the Dominican Republic). Most travelers are not at high risk for getting cholera but those traveling high risk areas should take steps to prevent getting sick. Although no cholera vaccine is available in the United States, travelers can greatly reduce their risk for cholera by following safe food and water advice: 
  • Before departing, talk to your doctor about getting a prescription for an antibiotic to treat travelers’ diarrhea. 
  • Drink only bottled, boiled, or chemically treated water and bottled or canned carbonated beverages. When using bottled drinks, make sure that the seal has not been broken. 
  • To disinfect your own water: boil for 1 minute or filter the water and add 2 drops of household bleach or ½ an iodine tablet per liter of water. 
  • Avoid tap water, fountain drinks, and ice cubes. 
  • Do not put ice in drinks, unless the ice is made from boiled or treated water. 
  • Eat only foods that have been thoroughly cooked and are still hot, or fruit that you have peeled yourself. 
  • Do not eat undercooked or raw fish or shellfish, including ceviche. 
  • Make sure all vegetables are cooked. Do not eat salads or other raw vegetables. 
  • Do not eat foods or drink beverages from street vendors. 
  • Do not bring perishable seafood back to the United States. 
  • Wash your hands often with soap and clean water, especially before preparing or eating food or after using the bathroom. If no water and soap are available, use an alcohol-based hand cleaner (with at least 60% alcohol). 
  • Use bottled, boiled, or chemically treated water to wash dishes, brush your teeth, wash and prepare food, or make ice. 
  • Eat foods that are packaged or that are freshly cooked and served hot. 
A simple rule of thumb for safe food and water is "Boil it, cook it, peel it, or forget it." 


Boston Public Health Commission
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