Information from CDC
Frequently Asked Questions
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.
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
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.
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.
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
- 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 cookedavoid salads.
- Avoid foods and beverages from street vendors.
- Do not bring perishable seafood back to the United States.
A simple rule of thumb is "Boil it, cook it, peel it, or forget it.
Distillation is the ONLY process that BOILS the water.
Health departments around the world agree that boiling the water is the
most fundamental way to kill biological contaminants. In distillation you
only take the pure steam that comes off the water, thus leaving the dead
bacteria and other contaminants behind! This process produces consistent
results year after year.
a vaccine available to prevent cholera?
At the present time, the manufacture and sale of the only licensed cholera
vaccine in the United States (Wyeth-Ayerst) has been discontinued. It has
not been recommended for travelers because of the brief and incomplete
immunity if offers. No cholera vaccination requirements exist for entry or
exit in any country.
Two recently developed vaccines for cholera are licensed and available
in other countries (DukoralŪ, Biotec AB and MutacolŪ, Berna). Both
vaccines appear to provide a somewhat better immunity and fewer
side-effects than the previously available vaccine. However, neither of
these two vaccines is recommended for travelers nor are they available in
the United States.
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
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
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. The number is 877-FYI-TRIP (394-8747) .