cholera

synonym

Biliary diarrhea (Greek)

definition

The cholera is a serious infectious disease that mainly causes severe diarrhea. The disease is triggered by Vibrio cholerae, one gram negative Bacterium that can be transmitted to humans through contaminated drinking water or food. The cholera occurs mainly in countries with inadequate hygienic conditions, where, above all, adequate food, drinking water and personal hygiene is not guaranteed. If left untreated, cholera can quickly lead to death as the Small intestine quickly leads to extreme electrolyte and thus water losses through the bacteria.Even the suspicion of cholera must be reported to the World Health Organization WHO be reported.

Epidemiology

Particularly affected are populous countries with a lack of separation of drinking water and sewage systems, e.g. South America, Africa and parts of Southeast Asia. The pathogens are occasionally introduced into Germany, so that cholera cases are rarely reported here as well. For tourists from industrialized countries, the risk of infection is quite low, as cholera mainly occurs in people who are already ill and have a poor nutritional status. Every year there are around 6 million cases with more than 100,000 deaths worldwide.

history

Probably it is cholera known since the 6th century BC. The disease spread from India to Europe much later, around 1800. So far one speaks of 7 Cholera pandemics. Discovered in 1883 Robert Koch the pathogen of cholera by culturing it from small intestine cells of patients who died of cholera. At the moment one speaks of the so-called El Tor pandemicwhich has been making circles in Africa, Southeast Asia since 1961 and also in Peru, South America since the 1990s. In 1992 a new subtype (Serotype) of the cholera pathogen with the name "Bengal“, Which led to outbreaks of varying strength, especially in Asia.

causes

The cholera is caused by the gram negative bacteria Vibrio cholerae that can be found in contaminated drinking water, food or in seafood contaminated with faeces. In addition, humans can be directly infected with pathogens that are excreted by other carriers through the stool, which is, however, rather rare. Infection is still possible up to a few weeks after infection, as pathogens can still be excreted in the stool for a long time. These then end up in the wastewater and the groundwater. A high number of bacteria in the small intestine is necessary for the disease to break out. Since this is often not achieved, the disease is symptom-free in around 85% of cases. The cholera bacteria produce a poison, the cholera toxin, which activates a certain enzyme in the small intestine. This leads to a reduced activity of certain salt pumps in the small intestine and thus to an increased excretion of electrolytes such as sodium, potassium and chloride. As these electrolytes draw huge amounts of water into the small intestine, the typical severe diarrhea occurs. What is feared here is the rapid dehydration (desiccosis) due to the extreme loss of water of up to 20 liters per day, which without treatment can lead to death within hours.

You can find a detailed overview of all tropical diseases under the article: Overview page on tropical diseases

Symptoms

After being infected with cholera, the disease breaks - if enough pathogens are found in the small intestine - with an incubation time of only a few hours up to 5 days out. One differentiates between a light form and a severe form. While the light form - too Cholerins called- often cannot be differentiated from other mild diarrheal diseases, the severe form is life-threatening and requires immediate treatment. Cholera suddenly begins with severe diarrhea, which is caused by Vomit and stomach pain can be accompanied. The diarrhea has a characteristic appearance: One speaks of rice water stools, as the stools are interspersed with whitish flakes of mucus and thus resemble the color of rice. The heavy loss of fluid soon leads to acute dehydration (desiccosis and dehydration), which manifests itself in standing skin folds, sunken eyeballs, dry mucous membranes and constantly falling body temperature. Furthermore, if left untreated, cholera will eventually lead to circulatory failure. Of the Pulse flattens off sharply, blood pressure falls and it can lead to shock at the same time Kidney failure come. The extreme electrolyte losses often cause severe ones Muscle spasms and let the metabolism derail at some point up to and including impaired consciousness coma can enter.

diagnosis

The diagnosis of cholera is provided on the basis of the typical clinical symptoms together with the pathogen detection from the stool or vomit of the person concerned. However, you should not wait to start treatment until the laboratory result is available, as important time is lost here. Rather, it should if cholera is suspected therapy, especially fluid replacement, can be started immediately. Even suspicion of the disease has to be reported to the World Health Organization and a bacteriologist has to be called in. When transporting the samples to the laboratory, care must be taken to keep the samples moist, as the pathogens are sensitive to dryness. If the diagnosis is positive, the curved and mobile bacteria can be observed en masse in the microscopic specimen. In general, two different subgroups (Serotypes) of cholera bacteria: O1 such as O139but both are treated equally.

therapy

Should there be any suspicion cholera occur, immediate isolation in the single room and an immediate start of therapy is essential. In the first place, fluid and electrolyte loss should be corrected to avoid complications such as Cycle- and prevent kidney failure. If substitution is rapid and sufficient, mortality can be greatly reduced. Both drinking and infusion solutions are available for fluid replacement. In general, infusion solutions are preferable, but these are often not available in sufficient quantities, especially in third world countries. That's what the WHO a recommendation to mix a drinking solution was given. This mainly consists of table salt dissolved in water (Sodium chloride) and glucose (glucose) and other electrolytes such as potassium. Glucose is given because sodium is absorbed into the cells together with the glucose in the intestine. Sodium pulls water with it, which reduces fluid loss.

In addition to the fluid balance, an antibiotic is administered that kills the bacteria, but does not significantly improve the course of the disease. Only the duration of the infectiousness is shortened by the drug. One uses quinolone or macolide preparations.

See also: Diet for diarrhea

prophylaxis

In the first place it should be sufficient Drinking water hygiene stand. If a supply of hygienically pure drinking water cannot be guaranteed, the water must be filtered or boiled. Food such as fruit should only be eaten peeled. It is also best to quarantine infected people in single rooms so that further infections are prevented. There is the possibility of an active Vaccination. This means that killed cholera bacteria are administered in order to achieve immunization. The killed bacteria are no longer able to trigger the disease. However, the vaccination does not offer complete protection and has not yet been approved in Germany. The protection lasts between three and six months up to a maximum of two years. Vaccination is generally not recommended for tourists traveling to risk areas. However, it is currently being discussed whether the vaccination against the much more common Traveler's diarrheacaused by the bacterium Toxin-producing Escherichia coli (ETEC) is caused. In addition, a vaccination is required in some countries before entering the country.

A live vaccine is also currently on the market. The vaccine is given orally as two oral vaccinations. However, it is important to note that no vaccine has yet been found that protects against cholera type O 139.

forecast

With correct therapy, the mean death rate is only 1-5%However, if the therapy starts too late or if it is neglected, it rises up to 60%. People who are already weakened and have reduced health are particularly at risk health status.

Summary

The cholera is a seriously life-threatening disease in and of itself, but if it is recognized as such early and its symptoms are treated quickly, the probability of survival is very high. The main problem is probably the inadequate sewage supply in the affected areas. Therefore, so far the only valuable measure to prevent cholera is one consistent hygiene. It is also interesting that people with blood group 0 are one seemingly have a higher risk of developing cholera than carriers of blood group AB. However, details have not yet been clarified.