Vibrio cholerae bacteria are typically responsible for the diarrheal illness called cholera. The two different types are Vibrio cholerae Serogroup O1 and Vibrio cholerae Serogroup non-O1. A person can get cholera by drinking water or eating food contaminated with this bacteria.
What Is Vibrio Cholerae ?
Vibrio cholerae is a type of bacteria that cause
cholera (an acute, diarrheal illness that can result in severe dehydration and even death within a matter of hours). These are Gram-negative rods
(see Pictures of Cholera) that are facultatively anaerobic, which means they can survive either with or without oxygen.
There are two general types of
Vibrio cholerae:
- Vibrio cholerae Serogroup O1
- Vibrio cholerae Serogroup non-O1.
Vibrio cholerae Serogroup O1 is the bacteria that is most often the
cause of cholera.
Vibrio cholerae Serogroup O139, a
Vibrio cholerae Serogroup non-O1 bacterium, is the other cause of cholera. There are about 70 other species of
Vibrio cholerae Serogroup non-O1; these other species rarely cause
diarrhea.
The bacteria is native to the Ganges delta, which is in India and extends into Bangladesh. Since 1817, there have been seven worldwide
pandemics. There is an ongoing global pandemic in Asia, Africa, and Latin America that has lasted more than four decades. Since 1995, over 80 percent of reported cases have occurred in Africa.
Vibrio cholerae infections have been rare in industrialized nations for the last 100 years. In the United States, there are zero to five cases per year.
In 2003, 111,575 cases from 45 countries were reported to the World Health Organization.
Transmission of Vibrio Cholerae
A person may get
cholera by drinking water or eating food contaminated with
Vibrio cholerae. In an epidemic, the source of contamination is usually the feces of an infected person. Cholera can spread rapidly in areas with inadequate treatment of sewage and drinking water.
Vibrio cholerae may also live in the environment in brackish rivers and coastal waters. Shellfish, when eaten raw, have been a source of contamination, and a few people in the United States have contracted cholera after eating raw or undercooked shellfish from the Gulf of Mexico.
Vibrio cholerae 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.
Once
Vibrio cholerae is ingested, the bacteria travel to the small intestine, where they begin to multiply. The bacteria then begins producing its toxin, which is the main cause of watery
diarrhea, a characteristic symptom of cholera.
A person needs to ingest a lot of
Vibrio cholerae in order to develop
symptoms of cholera. The amount needed is decreased in those taking
antacids, or following a meal, when the acids in the stomach are neutralized.
