Cholera

Is an infection in the small intestine caused by the bacterium vibrio cholorae.

The main symptoms are profuse, watery diarrhea and vomiting. Transmission occurs primarily by drinking water or eating food that has been contaminated by the feces of an infected person, including one with no apparent symptoms. The severity of the diarrhea and vomiting can lead to rapid dehydration andelectrolyte imbalance, and death in some cases.


The primary treatment is oral rehydration therapy, typically with oral rehydration solution (ORS), to replace water and electrolytes. If this is not tolerated or does not provide improvement fast enough, intravenous fluids can also be used.


Antibacterial drugs are beneficial in those with severe disease to shorten its duration and severity. Worldwide, it affects 3–5 million people and causes 100,000–130,000 deaths a year as of 2010. Cholera was one of the earliest infections to be studied by epidemiological methods.


Taken from:http://en.wikipedia.org/wiki/Cholera

A short animated film produced by the Global Health Media Project

History of Cholera in an African country, which are symptoms and other things about cholera.

Signs and symptoms

The primary symptoms of cholera are profuse, painless diarrhea and vomiting of clear fluid. These symptoms usually start suddenly, one to five days after ingestion of the bacteria. The diarrhea is frequently described as "rice water" in nature and may have a fishy odor. An untreated person with cholera may produce 10–20 litres of diarrhea a day with fatal results. For every symptomatic person, 3 to 100 people get the infection but remain asymptomatic. Cholera has been nicknamed the "blue death" due to a patient's skin turning a bluish-gray hue from extreme loss of fluids.

If the severe diarrheoea is not treated with intravenous rehydration, it can result in life-threatening dehydration and electrolyte imbalances. The typical symptoms of dehydration include low blood pressure, poor skin turgor (wrinkled hands), sunken eyes, and a rapid pulse.

Taken from: http://en.wikipedia.org/wiki/Cholera

Figure 1: Rice-water stool from a patient with cholera; note the flecks of mucus precipitated at the bottom of the cup that resemble rice grains. SOURCE: CDC













Figure 2: Washer woman hands (loss of skin elasticity) are a sign of the dehydration seen in cholera. SOURCE: CDC

What causes cholera, and how is cholera transmitted?

Cholera is caused by the bacterium V. cholerae. This bacterium is Gram stain-negative and has a flagellum (a long, tapering, projecting part) for motility and pili (hairlike structures) used to attach to tissue. Although there are many V. choleraeserotypes that can produce cholera symptoms, the O groups O1 and O139, which also produce a toxin, cause the most severe symptoms of cholera. O groups consist of different lipopolysaccharides-protein structures on the surface of bacteria that are distinguished by immunological techniques. The toxin produced by these V. cholerae serotypes is an enterotoxin composed of two subunits, A and B; the genetic information for the synthesis of these subunits is encoded on plasmids (genetic elements separate from the bacterial chromosome). In addition, another plasmid type encodes for a pilus (a hollow hairlike structure that can augment bacterial attachment to human cells and facilitate the movement of toxin from V. cholerae into human cells). The enterotoxin causes human cells to extract water and electrolytes from the body (mainly the upper gastrointestinal tract) and pump it into the intestinal lumen where the fluid and electrolytes are excreted as diarrheal fluid. The enterotoxin is similar to toxin formed by bacteria that cause diphtheria in that both bacterial types secret the toxins into their surrounding environment where the toxin then enters the human cells. The bacteria are usually transmitted by drinking contaminated water, but the bacteria can also be ingested in contaminated food, especially seafood such as raw oysters.

Taken of: http://www.medicinenet.com/cholera/page3.htm

What is the history of cholera?

Cholera has likely been with humans for many centuries. Reports of cholera-like disease have been found in India as early as 1000 AD. Cholerais a term derived from Greek khole (illness from bile) and later in the 14th century to colere (French) and choler (English). In the 17th century, cholerawas a term used to describe a severe gastrointestinal disorder involving diarrhea and vomiting. There were many outbreaks of cholera, and by the 16th century, some were being noted in history. England had several in the 18th century, most notable being in 1854, when Dr. John Snow did a classic study in London that showed a main source of the disease (resulting in about 500 deaths in 10 days) came from at least one of the major water sources for London residents termed the "Broad Street pump." The pump handle was removed, and the cholera deaths slowed and stopped. The pump is still present as a landmark in London. Although Dr. Snow did not discover the cause of cholera, he did show how the disease could be spread and how to stop a local outbreak. This was the beginning of modern epidemiologic studies. The last reference shows the map Dr. Snow used to identify the pump site.

V. cholerae was first isolated as the cause of cholera by Filippo Pacini in 1854, but his discovery was not widely known until Robert Koch (who also discovered the cause of tuberculosis), working independently 30 years later, publicized the knowledge and the means of fighting the disease. The history of cholera repeats itself. The U.S. National Library of Medicine houses original documents about multiple cholera outbreaks in the U.S. from the 1820s to the 1900s, with the last large outbreak in 1910-1911. Since the 1800s, there have been seven cholera pandemics (worldwide outbreaks).

Cholera riots occurred in Russia and England (1831) and in Germany (1893) when the people rebelled against strict government isolation (quarantines) and burial rules. In 2008, cholera riots broke out in Zimbabwe as police tried to disperse people who tried to withdraw funds from banks and were protesting because of the collapse of the health system that began with a cholera outbreak. Similar but less violent public protests have occurred when yellow fever, typhoid fever, and tuberculosis quarantines have been enforced by health authorities.

Multiple outbreaks worldwide continue into the 21st century with outbreaks in India, Iran, Vietnam, and several African countries occurring over the last 10 years (most recent outbreaks occurred in Haiti and Nigeria in 2010-2011). Why is cholera history repeating itself? The answer can be traced back to Dr. Snow's studies that show a source (water or occasionally food) contaminated with V. cholerae can easily and rapidly transmit the cholera-causing bacteria to many people. Until safe water and food is available to all humans, it is likely that cholera outbreaks will continue to happen.

Taken from: http://www.medicinenet.com/cholera/page3.htm

Water In The Time Of Cholera: Haiti's Most Urgent Health Problem

After the earthqueake produced in 2010

How is cholera diagnosed?

Preliminary diagnosis is usually done by a caregiver who takes a history from the patient and observes the characteristic rice-water diarrhea, especially if a local outbreak of cholera has been identified. The diarrhea fluid is often teeming with motile, comma-shaped bacteria (presumptively V. cholerae) that can be seen with a microscope. The definitive diagnosis is made by isolation of the bacteria from diarrhea fluid on a selective medium thiosulfate-citrate-bile salts agar (TCBS). Reagents for serogrouping Vibrio cholerae isolates are available in all state health department laboratories in the U.S. Readers may see terms like serotypes Inaba, Ogawa, and Hikojima to describe V. cholerae; they simply indicate which O antigens (O antigens designated A, B, or C) are found on these strains of V. cholerae. PCR tests have also been developed to detect the genetic material of cholera, but currently they are not as widely used as the immunologic tests based on type-specific antiserum.

Definitive diagnosis helps to distinguish cholera from other diseases caused by other bacterial, protozoal, or viral pathogens that cause dysentery (gastrointestinal inflammation with diarrhea).

From: http://www.medicinenet.com/cholera/page5.htm

Treatment

Continued eating speeds the recovery of normal intestinal function. The World Health Organization recommends this generally for cases of diarrhea from whatever cause. A CDC training manual specifically for cholera states: “Continue to breastfeed your baby if the baby has watery diarrhea, even when traveling to get treatment. Adults and older children should continue to eat frequently.

[edit]Fluids

In most cases, cholera can be successfully treated with oral rehydration therapy (ORT), which is highly effective, safe, and simple to administer. Rice-based solutions are preferred to glucose-based ones due to greater efficiency. In severe cases with significant dehydration, intravenous rehydration may be necessary. Ringer's lactate is the preferred solution, often with added potassium. Large volumes and continued replacement until diarrhea has subsided may be needed. Ten percent of a person's body weight in fluid may need to be given in the first two to four hours. This method was first tried on a mass scale during the Bangladesh Liberation War, and was found to have much success.

If commercially produced oral rehydration solutions are too expensive or difficult to obtain, solutions can be made. One such recipe calls for 1 litre of boiled water, 1/2 teaspoon of salt, 6 teaspoons of sugar, and added mashed banana for potassium and to improve taste.

[edit]Electrolytes

As there frequently is initially acidosis, the potassium level may be normal, even though large losses have occurred. As the dehydration is corrected, potassium levels may decrease rapidly, and thus need to be replaced.

[edit]Antibiotics

Antibiotic treatments for one to three days shorten the course of the disease and reduce the severity of the symptoms. People will recover without them, however, if sufficient hydration is maintained. Doxycycline is typically used first line, although some strains of V. cholerae have shown resistance. Testing for resistance during an outbreak can help determine appropriate future choices. Other antibiotics proven to be effective include cotrimoxazole, erythromycin, tetracycline, chloramphenicol, and furazolidone.Fluoroquinolones, such as norfloxacin, also may be used, but resistance has been reported.

In many areas of the world, antibiotic resistance is increasing. In Bangladesh, for example, most cases are resistant to tetracycline, trimethoprim-sulfamethoxazole, and erythromycin. Rapid diagnostic assay methods are available for the identification of multiple drug-resistant cases. New generation antimicrobials have been discovered which are effective against in in vitro studies.

[edit]Sari filtration

An effective and relatively cheap method to prevent transmission of V. cholera is the practice of folding a sari (a long fabric garment) multiple times to create a simple filter for drinking water. Folding saris four to eight times may create a simple filter to reduce the amount of active V. cholera in the filtered water. The education of proper sari filter use is imperative, as there is a positive correlation between sari misuse and the incidence of childhood diarrhea; soiled saris worn by women are vectors of transmission of enteric pathogens to young children. Educating at-risk populations about the proper use of the sari filter method may decrease V. cholera-associated disease.






Taken from:http://en.wikipedia.org/wiki/Cholera

Treatment

WHO Fluid Replacement or Treatment Recommendations (as per the CDC)

Patient condition	Treatment	Treatment volume guidelines; age and weight
No dehydration	Oral rehydration salts (ORS)	Children < 2 years: 50 mL-100 mL, up to 500 mL/day Children 2-9 years: 100 mL-200 mL, up to 1,000 mL/day Patients > 9 years: As much as wanted, to 2,000 mL/day
Some dehydration	Oral rehydration salts (amount in first four hours)	Infants < 4 mos (< 5 kg): 200-400 mL Infants 4 mos-11 mos (5 kg-7.9 kg): 400-600 mL Children 1 yr-2 yrs (8 kg-10.9 kg): 600-800 mL Children 2 yrs-4 yrs (11 kg-15.9 kg): 800-1,200 mL Children 5 yrs-14 yrs (16 kg-29.9 kg): 1,200-2,200 mL Patients > 14 yrs (30 kg or more): 2,200-4,000 mL
Severe dehydration	IV drips of Ringer Lactate or, if not available, normal saline and oral rehydration salts as outlined above	Age < 12 months: 30 mL/kg within one hour*, then 70 mL/kg over five hours Age > 1 year: 30 mL/kg within 30 min*, then 70 mL/kg over two and a half hours