Information on Cholera

What is cholera?
Cholera is an acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae. The infection is often mild or without symptoms, but sometimes it can be severe. Approximately one in 20 infected persons has severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps. In these persons, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

How does a person get cholera?
A person may get cholera by drinking water or eating food contaminated with the cholera bacterium. In an epidemic, the source of the contamination is usually the feces of an infected person. The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water.

The cholera bacterium may also live in the environment in brackish rivers and coastal waters. Shellfish eaten raw have been a source of cholera, and a few persons in the United States have contracted cholera after eating raw or undercooked shellfish from the Gulf of Mexico. 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 is the risk for cholera in the United States?
In the United States, cholera has been virtually eliminated by modern sewage and water treatment systems. U.S. travelers to areas with epidemic cholera may be exposed to the cholera bacterium.

What should travelers do to avoid getting cholera?
The risk for cholera is very low for U.S. travelers visiting areas with epidemic cholera. When simple precautions are observed, contracting the disease is unlikely. A simple rule of thumb is "Boil it, cook it, peel it, or forget it. "

All travelers to areas where cholera has occured should observe the following recommendations:

• Drink only water that you have boiled or treated with chlorine or iodine. Other safe beverages include tea and coffee made with boiled water and carbonated, bottled beverages with no ice.
• Eat only foods that have been thoroughly cooked and are still hot, or fruit that you have peeled yourself.
• Avoid undercooked or raw fish or shellfish, including ceviche.
• Make sure all vegetables are cooked avoid salads.
• Avoid foods and beverages from street vendors.
• Do not bring perishable seafood back to the United States.

Is a vaccine available to prevent cholera?
No cholera vaccination requirements exist for entry or exit in any country.

Can cholera be treated?
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. With prompt rehydration, fewer than 1% of cholera patients die.

Antibiotics shorten the course and diminish the severity of the illness, but they are not as important as rehydration. Persons who develop severe diarrhea and vomiting in countries where cholera occurs should seek medical attention promptly.

Where can a traveler get information about cholera?
The global picture of cholera changes periodically, so travelers should seek updated information on countries of interest. The Centers for Disease Control and Prevention maintains a travelers' information telephone line on which callers can receive recent information on cholera and other diseases of concern to travelers. Data for this service are obtained from the World Health Organization. The number is 877-FYI-TRIP (394-8747) or check out http://www.cdc.gov/travel.

Source: Centers for Disease Control and Prevention, June 13, 2006