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Cholera
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(or ''Asiatic cholera'' or ''epidemic cholera'') is a severe
Diarrhea l disease caused by the
Bacterium ''
Vibrio Cholerae ''.
1 Transmission to humans is by ingesting contaminated water or food. The major reservoir for cholera was long assumed to be humans, but some evidence suggests that it is the aquatic environment.
''V. cholerae'' is a within an hour of the onset of symptoms and may die within 2-3 hours if no treatment is provided. More commonly, the disease progresses from the first liquid stool to shock in 4-12 hours, with death following in 18 hours to several days without rehydration treatment.
2 WHO Cholera
{Link without Title}
The U.N. reported recently of a Cholera outbreak in Iraq.
3
Symptoms include those of general GI tract (stomach) upset and
Massive Watery Diarrhea . Symptoms may also include terrible muscle and stomach cramps, vomiting and fever in early stages. In a later stage the diarrhea becomes "rice water stool" (almost clear with flecks of white). Symptoms are caused by massive body fluid loss induced by the
Enterotoxin s that ''V. cholerae'' produces. The main enterotoxin, known as , interacts with
G Protein s and
Cyclic AMP in the intestinal lining to open
Ion Channels . As ions flow into the intestinal
Lumen (lining), body fluids (mostly water) flow out of the body due to
Osmosis leading to massive diarrhea as the fluid is expelled from the body. The body is "tricked" into releasing massive amounts of fluid into the small intestine which shows up in up to 36 liters of liquid diarrhea in a six day period in adults with accompanying massive dehydration.
4 Radical dehydration can bring death within a day through collapse of the circulatory system.
In general, patients must receive as much fluid as they lose, which can be up to 36 L, due to diarrhea.
Treatment typically consists of aggressive for easily made rehydration solutions and
Ceralyte . Without rehydration, the death rate can be as high as (10-50%) due to the serious dehydration that cholera produces.
Tetracycline Antibiotics may have a role in reducing the duration and severity of cholera, although drug-resistance is occurring.
5 Oral tetracycline was recommended for reducing the period of vibrio excretion and need for parenteral fluid. Initially cholera vibrios were universally susceptible to all antibiotics active against gram negative bacilli, but since 1979 multiple drug resistant strain have become increasingly common and their effects on overall mortality are questioned.
6 Other antibiotics that have been used include
Ciprofloxacin and
Azithromycin ,
7 although again, drug-resistance has now been described.
8
Without treatment the death rate is as high as 50%; with treatment the death rate can be well below 1%.
9
Although cholera can be life-threatening, it is nearly always easily prevented, in principle, if proper sanitation practices are followed. In the United States and Western Europe, because of advanced water treatment and sanitation systems, cholera is no longer a major threat. The last major outbreak of cholera in the United States was in
1911 . However, everyone, especially travelers, should be aware of how the disease is transmitted and what can be done to prevent it. Good sanitation practices, if instituted in time, is usually sufficient to stop an epidemic. There are several points along the transmission path at which the spread may be halted:
- Sickbed: Proper disposal and treatment of the germ infected fecal waste (and all clothing and bedding that come in contact with it) produced by cholera victims is of primary importance.
- Sewage: Treatment of general sewage before it enters the waterways or underground water supplies prevent possible undetected patients from spreading the disease.
- Sources: Warnings about cholera contamination posted around contaminated water sources with directions on how to decontaminate the water.
- Sterilization: Boiling, filtering, and chlorination of water kill the bacteria produced by cholera patients and prevent infections, when they do occur, from spreading. All materials (clothing, bedding, etc.) that come in contact with cholera patients should be sterilized in hot water using (if possible) chlorine bleach. Hands, etc. that touch cholera patients or their clothing etc. should be thoroughly cleaned and sterilized. All water used for drinking, washing or cooking should be sterilized by boiling or chlorination in any area where cholera may be present. Water filtration, chlorination and boiling are by far the most effective means of halting transmission. Cloth Filter s, though very basic, have greatly reduced the occurrence of cholera when used in poor villages in Bangladesh that rely on untreated surface water. In general, public health education and good sanitation practices are the limiting facters in preventing transmission.
Recent are the most susceptible,
1011 while those with
Type AB are the most resistant. Between these two extremes are the A and B blood types, with type A being more resistant than type B.
About one million ''V. cholerae'' bacteria must typically be ingested to cause cholera in normally healthy adults, although increased susceptibility may be observed in those with a weakened
Immune System , individuals with decreased gastric acidity (as from the use of
Antacid s), or those who are
Malnourished .
It has also been hypothesized that the carriers of the mutation (who are thus not affected by cystic fibrosis) are more resistant to ''V. cholerae'' infections.
12 In this model, the genetic deficiency in the
Cystic Fibrosis Transmembrane Conductance Regulator channel proteins interferes with bacteria binding to the
Gastrointestinal epithelium, thus reducing the effects of an infection.
of
Death bringing the cholera, in ''
Le Petit Journal ''.]]
Persons infected with cholera have massive diarrhea. This highly liquid
Diarrhea , which is often compared to "rice water," is loaded with bacteria that can spread under unsanitary conditions to infect water used by other people. Cholera is transmitted from person to person through ingestion of
Feces contaminated water loaded with the cholera bacterium. The source of the contamination is typically other cholera patients when their untreated diarrhea discharge is allowed to get into waterways or into
Groundwater or drinking water supply. Any infected water and any foods washed in the water, and
Shellfish living in the affected
Waterway can cause an infection. Cholera is rarely spread directly from person to person. ''V. cholerae'' occurs naturally in the
Plankton of
Fresh ,
Brackish , and
Salt Water , attached primarily to
Copepod s in the
Zooplankton . Both toxic and non-toxic strains exist. Non-toxic strains can acquire toxicity through a
Lysogenic Bacteriophage .
13 Coastal cholera outbreaks typically follow
Zooplankton Blooms . This makes cholera a
Zoonosis .
Stool and Swab collected in the acute stage of the disease are useful specimens for laboratory diagnosis. A number of special media have been employed for the cultivation for cholera vibrios. They are classified as follows:
#''Venkataraman-ramakrishnan (VR) medium''
#''Cary-Blair medium'': This the most popularly carrying media. This is a buffered solution of sodium chloride, sodium thioglycollate, disodium phosphate and calcium chloride at pH 8.4.
#''Alkaline peptone water''
#''Monsur's taurocholate tellurite peptone water''
#''Alkaline bile salt agar'': The colonies are very similar to those on Nutrient Agar.
#''Monsur's gelatin Tauro cholate trypticase tellurite agar (GTTA) medium'': Cholera vibrios produce small translucent colonies with a greyish black centre.
#''TCBS medium'': This the mostly widely used medium. This medium contains thiosulphate, citrate, bile salts and sucrose. Cholera vibrios produce flat 2-3 mm in diameter, yellow nucleated colonies.
Most of the ''V. cholerae'' bacteria in the contaminated water that a potential host drinks do not survive the very acidic conditions of the to make toxin proteins in cholera bacteria as a "comprehensive example" of what is known about the mechanisms by which bacteria change the mix of proteins they manufacture to respond to the changing opportunities for surviving and thriving in different chemical environments). But the few bacteria that manage to survive the stomach's acidity conserve their
Energy And Stored Nutrients during the perilous passage through the stomach by shutting down much protein production. When the surviving bacteria manage to exit the stomach and reach the favorable conditions of the
Small Intestine , they need to propel themselves through the thick
Mucus that lines the small intestine to get to the intestinal wall where they can thrive. So they start up production of the hollow cylindrical protein
Flagellin to make
Flagella , the curly whip-like tails that they rotate to propel themselves through the pasty mucus that lines the small intestine.
Once the cholera bacteria reach the intestinal wall, they do not need the flagella propellers to move themselves any more, so they stop producing the protein flagellin, thus again conserving energy and nutrients by changing the mix of proteins that they manufacture, responding to the changed chemical surroundings. And on reaching the intestinal wall, they start producing the toxic proteins that give the infected person a watery
Diarrhea which carries the multiplying and thriving new generations of ''V. cholerae'' bacteria out into the drinking water of the next host—if proper sanitation measures are not in place.
Microbiologists have studied the
Genetic Mechanisms by which the ''V. cholerae'' bacteria turn off the production of some proteins and turn on the production of other proteins as they respond to the series of chemical environments they encounter, passing through the stomach, through the mucous layer of the small intestine, and on to the intestinal wall.
14 Of particular interest have been the genetic mechanisms by which cholera bacteria turn on the protein production of the toxins that ineract with host cell mechanisms to pump
Chloride ions into the small intestine, creating an ionic pressure which prevents sodium ions from entering the cell. The choride and sodium ions create a salt water environment in the small intestines which through osmosis can pull up to six liters of water per day through the intestinal cells creating the massive amounts of diarrhea. The host can become rapidly dehydrated if an appropriate mixture of dilute salt water and sugar is not taken to replace the blood's water and salts lost in the diarrhea.
By inserting separately, successive sections of ''V. cholerae'' DNA into the DNA of other bacteria such as ''
E. Coli '' that would not naturally produce the protein toxins, researchers have investigated the mechanisms by which ''V. cholerae'' responds to the changing chemical environments of the stomach, mucous layers, and intestinal wall. Researchers have discovered that there is a complex cascade of regulatory proteins that control expression of ''V. cholerae'' virulence determinants. In responding to the chemical environment at the intestinal wall, the ''V. cholerae'' bacteria produce the TcpP/TcpH proteins which, together with the ToxR/ToxS proteins, activate the expression of the ToxT regulatory protein. ToxT then directly activates expression of virulence genes that produce the toxins that cause diarrhea in the infected person and that permit the bacteria to colonize the intestine. Current research aims at discovering "the signal that makes the cholera bacteria stop swimming and start to colonize (that is, adhere to the cells of) the small intestine."p. 574
Cholera was originally
Endemic to the Indian subcontinent, with the
Ganges River likely serving as a contamination reservoir. It spread by trade routes (land and sea) to
Russia , then to
Western Europe , and from Europe to
North America . It is now no longer considered an issue in Europe and North America, due to
Filtering and
Chlorination of the water supply.
- 1816-1826 - : Previously restricted, the pandemic began in Bengal , then spread across India by 1820. It extended as far as China and the Caspian Sea before receding.
- 1829-1851 - reached Europe, ), Quebec , Ontario and New York in the same year and the Pacific coast of North America by 1834.
- 1849 - Second major outbreak in Paris. In London, it was the worst outbreak in the city's history, claiming 14,137 lives, ten times as many as the 1832 outbreak. In 1849 cholera claimed 5,308 lives in the port city of Liverpool, England, and 1,834 in Hull, England.IBMS Institute of Biological Science An outbreak in North America took the life of former , Utah and Oregon .Trails of Hope: California, Oregon and Mormon Trails [http://overlandtrails.lib.byu.edu/ctrail.htm]
- 1852-1860 - mainly affected Russia, with over a million deaths. In 1853-4, London's epidemic claimed 10,738 lives.
- 1854 - Outbreak of cholera in Chicago took the lives of 5.5 per cent of the population (about 3,500 people). {Link without Title} . Soho outbreak in London stopped by removing the handle of the Broad Street Pump by a committee instigated to action by John Snow . On the Mode of Communication of Cholera (1855) by John Snow, M.D. (1813-1858) [http://eee.uci.edu/clients/bjbecker/PlaguesandPeople/week8a.html
- 1863-1875 - spread mostly in Europe and Africa .
- 1866 - Outbreak in North America. In London, a localized epidemic in the East End claimed 5,596 lives just as London was completing its major sewage and water treatment systems--the East End was not quite complete. William Farr, using the work of John Snow et al. as to contaminated drinking water being the likely source of the disease, was able to relatively quickly identify the East London Water Company as the source of the contaminated water. Quick action prevented further deaths. "The Ghost Map" by Steven Johnson, pg. 209
- 1881-1896 - ; The 1892 outbreak in Hamburg, Germany was the only major European outbreak; about 8,600 people died in Hamburg, causing a major political upheaval in Germany, as control over the City was removed from a City Council which had not updated Hamburg's water supplies. This was the last serious European cholera outbreak.
- 1899-1923 - had little effect in Europe because of advances in public health, but Russia was badly affected again.
- 1961-1970s - began in Indonesia , called El Tor after the strain, and reached Bangladesh in 1963, India in 1964, and the USSR in 1966. From North Africa it spread into Italy by 1973. In the late 1970s there were small outbreaks in Japan and in the South Pacific. There were also many reports of a cholera outbreak near Baku in 1972, but information about it was suppressed in the USSR.
- January 1991 to September 1994 - Outbreak in South America , apparently initiated when a ship discharged ballast water. Beginning in Peru there were 1.04 million identified cases and almost 10,000 deaths. The causative agent was an O1, El Tor strain, with small differences from the seventh pandemic strain. In 1992 a new strain appeared in Asia, a non-O1, Nonagglutinable Vibrio (NAG) named O139 Bengal. It was first identified in Tamil Nadu , India and for a while displaced El Tor in southern Asia before decreasing in prevalence from 1995 to around 10% of all cases. It is considered to be an intermediate between El Tor and the classic strain and occurs in a new Serogroup . There is evidence of the emergence of wide-spectrum resistance to drugs such as Trimethoprim , Sulfamethoxazole and Streptomycin .
The crying and pathos in the last movement of , including his brother
Modest 's idea that Tchaikovksy drank cholera infested water the day before he became ill).. However, this is not true according to Poznansky in his book "Tchaikovsky". Modeste and Tschaikovsky were very close loved each other dearly and got along very well. What acutally happen is that T. and Modeste had gone to the Theatre and afterwards went to a restaurant(Leiner's) for Supper. As was his custom; T. drank water with his meals. He ordered Pasta, his favorite dish, and bottled alkaline mineral water, which by itself was safe to drink although it neutralized stomach acids (sort of like Alka Seltzer today). Because of the expense involved in Bottle water (which was never brought to the table) many restaurants in St. Petersburg commited fraud and used tap water instead or iced the boiled mineral water with contaminated Ice from tap water. Law required all restaurants to boil water but many again cheated and did not do it or did not get the temperature high enough (200-212F). T. was served contaminated water at the restaurant and refused to see a Doctor at first until it was too late. Cholera symptoms were treated back then and not the disease.There would not have been anti-biotics available until the 1940s although it penicillin was discovered in 1920 and was not available in large quantities until the late 1930s. The alkaline mineral water neurtralized the stomach hydrochloric acid in the stomach thus aiding and abetting the slippage of the Cholorea organism through the stomach. Tchaikovsky's medical doctor was Dr.Vasily Bertenson whose bumbling aggravated T.'s condition. Dr.Berenson was blamed for T's death until he died although he did the best that he knew how including having his brother Lev, who was the Tzar's physician, help in the case. Bertenson was unable to diagnose T.s condtion because non of the diarhhea fluids had been saved and it took seeing the organisim under a microscope to give absolute proof of Cholera. It is true that T. knew he was dying. He lightly told Gluzanov, who was part of the Supper party, that he thought he was dying and that he had chlorea.
Other famous people who succumbed to the disease include:
- James K. Polk ex-President of the United States
- Mary Abigail Fillmore , daughter of U.S. president Millard Fillmore
- Elliott Frost, son of American poet Robert Frost
- Nicolas Léonard Sadi Carnot
- Georg Wilhelm Friedrich Hegel
- Samuel Charles Stowe, son of Harriet Beecher Stowe
- Carl Von Clausewitz
- George Bradshaw
- Adam Mickiewicz
- August Von Gneisenau
- William Jenkins Worth
- John Blake Dillon
- Daniel Morgan Boone, founder of Kansas City, Missouri , son of Daniel Boone
- James Clarence Mangan
- Mohammad Ali Mirza Dowlatshahi of Persia
- Ando Hiroshige , Japanese ukiyo-e woodblock print artist.
- Juan de Veramendi, Mexican Governor of Texas, father-in-law of Jim Bowie
- Grand Duke Constantine Pavlovich Of Russia
- William Shelley, son of Mary Shelley
- William Godwin, father of Mary Shelley
- Judge Daniel Stanton Bacon, father-in-law of George Armstrong Custer
- Inessa Armand , mistress of Lenin and the mother of Andre, his son.
- Honinbo Shusaku , famous go player.
- Henry Louis Vivian Derozio , Eurasian Portuguese Poet and Teacher. Resided in India.
Alexandre Dumas, Père , French author of
The Three Musketeers and
The Count Of Monte Cristo , also contracted cholera in the 1832 Paris epidemic and almost died, before he wrote these two novels.
The major contributions to fighting cholera were made by physician and self-trained scientist
John Snow (1813-1858), who found the link between cholera and contaminated drinking water in
1854 and Henry Whitehead, an Anglican minister, who helped John Snow track down and verify the source of the disease, an infected well in London. Their conclusions and writings were widely distributed and firmly established for the first time a definite link between germs and disease. Clean water and good sewage treatment, despite their major engineering and financial cost, slowly became a priority throughout the major developed cities in the world from this time onward.
Robert Koch , 30 years later, identified ''V. cholerae'' with a microscope as the bacillus causing the disease in 1885. The bacterium had been originally isolated thirty years earlier (1855) by Italian anatomist
Filippo Pacini , but its exact nature and his results were not widely known around the world.
Cholera has been a laboratory for the study of evolution of virulence. The province of Bengal in
British India was partitioned into
West Bengal (a state in India) and
East Pakistan in 1947. Prior to partition, both regions had cholera pathogens with similar characteristics. After 1947, India made more progress on public health than East Pakistan (now
Bangladesh ). As a consequence, the strains of the pathogen which succeeded in India had a greater incentive in the longevity of the host and are less virulent than the strains prevailing in Bangladesh, which uninhibitedly draw upon the resources of the host population, thus rapidly killing many in it.
In the past, people travelling in ships would hang a yellow flag if one or more of the crew members suffered from cholera. Boats with a yellow flag hung would not be allowed to disembark at any harbor for an extended period of time, typically 30 to 40 days.
15
A persistent myth states that
90,000 People Died In Chicago of cholera and
Typhoid Fever in 1885. This story has no factual basis. In 1885 there was a torrential rainstorm that flushed the Chicago river and its attendant pollutants into Lake Michigan far enough that the city's water supply was contaminated. Fortunately, cholera was not present in the city and this is not known to have caused any deaths. It did, however, cause the city to become more serious about their sewage treatment.
The term ''cholera morbus'' was used in the 19th and early 20th century to describe both non-epidemic cholera and gastrointestinal diseases that mimicked cholera. The term is not in current use, but is found in many older references.
Archaic Medical Terms.
