In January 1991, epidemic cholera appeared in South America and quickly spread to several countries. A few cases have occurred in the United States among persons who traveled to South America or ate contaminated food brought back by travelers.
Cholera has been very rare in industrialized nations for the last 100 years; however, the disease is still common today in other parts of the world, including the Indian subcontinent and sub-Saharan Africa.
Although cholera can be life-threatening, it is easily prevented and treated. In the United States, because of advanced water and sanitation systems, cholera is not a major threat; however, everyone, especially travelers, should be aware of how the disease is transmitted and what can be done to prevent it.
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 was prevalent in the 1800s but has been virtually eliminated by modern sewage and water treatment systems. However, as a result of improved transportation, more persons from the United States travel to parts of Latin America, Africa, or Asia where epidemic cholera is occurring. U.S. travelers to areas with epidemic cholera may be exposed to the cholera bacterium. In addition, travelers may bring contaminated seafood back to the United States; foodborne outbreaks have been caused by contaminated seafood brought into this country by travelers.
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.
All travelers to areas where cholera has occured should observe the following recomendations:
A simple rule of thumb is
"Boil it, cook it, peel it, or forget it. "
A vaccine for cholera is available; however, it confers only brief and incomplete immunity and is not recommended for travelers. There are no cholera vaccination requirements for entry or exit in any Latin American country or the United States.
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.
How long will the current epidemic last?
Predicting how long the epidemic in Latin America will last is difficult. The cholera epidemic in Africa has lasted more than 20 years. In areas with inadequate sanitation, a cholera epidemic cannot be stopped immediately, and there are no signs that the epidemic in the Americas will end soon. Latin American countries that have not yet reported cases are still at risk for cholera in the coming months and years. Major improvements in sewage and water treatment systems are needed in many of these countries to prevent future epidemic cholera.
What is the U.S. government doing to combat cholera?
U.S. and international public health authorities are working to enhance surveillance for cholera, investigate cholera outbreaks, and design and implement preventive measures. The Centers for Disease Control is investigating epidemic cholera wherever it occurs and is training laboratory workers in proper techniques for identification of V.cholerae. In addition, the Centers for Disease Control is providing information on diagnosis, treatment, and prevention of cholera to public health officials and is educating the public about effective preventive measures.
The U.S. Agency for International Development is sponsoring some of the international government activities and is providing medical supplies to affected countries.
The Environmental Protection Agency is working with water and sewage treatment operators in the United States to prevent contamination of water with the cholera bacterium.
The Food and Drug Administration is testing imported and domestic shellfish for V. cholerae and monitoring the safety of U.S. shellfish beds through the shellfish sanitation program.
With cooperation at the state and local, national, and international levels, assistance will be provided to countries where cholera is present, and the risk to U.S. residents will remain small.
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 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. This number is 404-332-4559.
Office of the Director, Mailstop C09
Division of Bacterial and Mycotic Diseases
National Center for Infectious Diseases
Centers for Disease Control
1600 Clifton Road
Atlanta, Georgia 30333
NCID Homepage
DBMD Homepage
Updated: Friday, August 9, 1996