Cholera-Past and Present “Of all pestilences cholera is perhaps the most awe inspiring: it may run so rapid a course that a man in good health at day break may be dead and buried ere nightfall.” (Marsden, 1992) This quote by P D Marsden gives a brief sense of just how serious the disease cholera can be. Cholera was a disease that ravished cities in the 19th century and is “still one of the most feared epidemic diseases today.” (Estrada-García & Mintz, 1996) Cholera is caused by the Vibrio cholerae bacterium and can have mild to severe symptoms, depending on how fast treatment is administered. It occurs more commonly in developing nations and is rare in developed countries. In the aftermath of large natural disasters, cholera is always a fear of public health officials. In the 19th century, cholera played a big role in the science of epidemiology. Cholera is caused by V. cholerae and can have mild to severe symptoms, occurs more commonly in developing nations, is a fear after large natural disasters, and played an important role in the science of epidemiology. Cholera is caused by a bacillus bacterium called Vibrio cholerae and was first cultured by Robert Koch in 1883. (“Cholera Epidemics in the 19th Century,” 2011) V. cholerae is a slightly unusual bacillus as it has a curved morphology giving it the appearance of a coma. It is a gram-negative bacterium and it posses a single polar flagellum. Man is the only known species that is able to host the V. cholerae bacteria. (Marsden, 1992) V. cholerae can be divided into serogroups. The serogroup O:1 is known as the classical strain and the serogroup O:139 is known as El Tor. Both have been identified as causes of cholera epidemics. The El Tor biotype is better adapted to food borne transmission than the classical biotype. (Estrada-García & Mintz, 1996) Because V. cholerae is so sensitive to acid, large doses of the bacterium are required to get the disease. The bacteria grow in the small intestine and release an exotoxin called cholera toxin. This toxin activates adenylcyclase, producing cyclic AMP. cAMP blocks sodium ion transportation and removes chloride ions and water from the blood into the intestine. This causes severe diarrhea and water loss. (Tortora, Funke, & Case, 2009) Dehydration can happen so quickly that the blood thickens and the skin turns blue, giving the victim a death-like appearance. (“Cholera Epidemics,” 2011) The blood can become so thick that vital organs are no longer able to function. The loss of the fluids and electrolytes can also cause the victim to go into shock. (Tortora, Funke, & Case, 2010) Other symptoms of cholera include abdominal cramps, dry mucus membranes, dry skin, excessive thirst, lack of tears, low urine output rapid pulse, and nausea. Once a person recovers from cholera they are immune to the disease for life by the same serotype they were infected with. However, they do become carriers of the disease.
The sudden loss of fluids and electrolytes poses a serious problem for the infected person. Fluids, in addition to electrolytes, must be administered quickly to ensure the recovery of the patient. Before the use of intravenous solutions to rehydrate, death rates for cholera were often as high as 70%. Fluids can also be given orally. Although cholera was a disease more common in the 19th century, oral rehydration therapy was not fully developed until the 1960s and 1970s. Oral rehydration therapy has been seen as one of the biggest medical triumphs of the 20th century. The development of ORT has significantly reduced death rates in diarrheal diseases such as cholera, especially among children. (Guerrant, Carneiro-Filho, & Dillingham, 2003) Now with proper care and treatment, death rates for cholera are less than 1%. (Tortora, Funke, & Case, 2010)
Today, cholera is no longer a problem in developed countries, but it is still a threat in developing nations. The sanitation revolution in the late 19th century and early 20th century