Cholera is transmitted through the fecal rolute(1). People may drink water having the bacterium. Third world countries which do not chlorinate water or wastewater have higher incidence of the disease. Vibrio cholera is a bacterium . It can live in fresh or salt water(1). It consists of gram negative straight or curved rods. It moves by one polar flagellum. It can do both respiratory or fermentative metabolism. (2). Identification from feces is possible because the bacterium high pH which kill other bacteria.(3). In bacteriology lab this semester we incubated a skin swab sample at 24 degrees C for 5 days and looked for cloudiness. This could be a good way to test for cholera activity in addition to the Gram Stain. Identification was made in 1883 by Robert Koch. Vibrio comes from the Latin word vibrate. Perhaps the flagellar movement caused the term vibrio.
The symptoms of the disease are diarhea and vomiting. A person could die within 24 hours if not given treatment. Treatment consists of constant rehydration with water, sugar and salts. Uganda had over 47,000 cases of cholera from 1977-1999(excuding the dead), according to Dr. Godfrey Browire, camp manager for Mulaga II cholera treatment center. Worldwide 1% of cases are fatal. Patients are housed in tents with cots and health workers spray with disinfectants when entering and leaving the tents. (4) Rains from El Nino and war nearby in the Republic of Congo lead to pollution with bacteria.
The mechanism of disease is this. The bacterium secretes endotoxin and exotoxin. These lead to salt excretion in the intestine which causes water build up and therefore diarhea and vomiting. In Latin America good sewage and water treatment with chlorine kills the bacterium. Antibiotics shorten the disease but is not as effective as fluid replacement. A vaccine is availabl;e but it gives only brief and incomplete immunity. Children have poor immune systems and many women are pregnant there. People are best to see a doctor in the few cases that develop in the U.S.A. "Emphasis is placed on the importannce of safe warer, scrupulous personal hygeine and careful food preparation"(5). In Bangladesh a PhD scientist, Rita Colwell, has been trying to teach the people to filter their water through gauze net. She believes Vibrio Cholera exists in spores (6). There are maybe 10 cases per year in the U.S.A.. These are usually at the Gulf of Mexico and arise from undercooking shellfish .
(I) Center for Disease Control and Prevention . http://www.cdc.gov/.
(2) http://www.bact.wisc.edu/Bact 330, lecture on cholera Bacteriology 330 Lecture Topics: Accessed 5-1-00.
(3)http:www.africanews.org/east/uganda/stories/1990129~feat 14 htoml. Distributed by Africa News Online
(4) Texas Dept. of Health. http://www.healthfinder. org., accessed 5-2-00
(5) world health org. http://www.who.ch/ (accessed 5-2-00)
(6)Dold, C. The Cholera Lesson., Discover 1999, February:71-75(accessed 4-30-00).