Cholera - clinic, diagnosis, prevention, treatment of an infectious disease. Cholera pathogenesis Principles of cholera treatment

This is an acute bacterial disease with an alimentary transmission mechanism, which is characterized by dyspeptic syndrome with severe dehydration.

History reference

The first mention of cholera appeared in the writings of ancient times. Hippocrates mentioned the symptoms characteristic of cholera in his writings. For the first time, a pure culture was isolated and studied by the German microbiologist Robert Koch in 1906. Cholera has claimed millions of lives throughout the history of mankind and accompanied all sorts of catastrophes and cataclysms (earthquakes, floods, wars). To date, isolated cases of cholera are recorded in disadvantaged areas of India. The causative agent of cholera was found in the water of the Sea of ​​Azov.

Etiology

The causative agent of cholera is Vibrio cholerae (Vibrio cholerae). This bacterium belongs to the genus of intestinal bacteria, curved (hence the name - vibrio), mobile, has flagella, spores and capsules does not form. There are 2 subspecies of Vibrio cholerae:

• classic - Vibrio cholerae classica;
• El Tor - Vibrio cholerae eltor.

The causative agent of cholera releases endotoxin during the death and destruction of the bacterial cell and heat-labile exotoxin - cholerogen, which causes dehydration of the body.

Vibrio cholerae is quite stable in the external environment in the presence of liquid. In wastewater, which have an alkaline environment, it can actively multiply. The El-Tor cholera subspecies is more resistant than the classical vibrio. Drying, exposure to direct sunlight, boiling, disinfectants, acidic environment are detrimental to the microorganism.

Epidemiology

Cholera is an anthroponotic infection, that is, its source is only a sick person or a bacteriocarrier. The causative agent is excreted from the body of a sick person from the first days of the disease with feces and vomit during vomiting. Of particular epidemiological danger are bacterial carriers and patients with an erased form of the disease, who do not seek medical help and continue to release Vibrio cholerae into the environment.

The mechanism of infection transmission is alimentary with water transmission. Outbreaks of cholera accompany poor sanitation during disasters, wars, natural disasters. There is a summer-autumn seasonality of the disease, which is associated with favorable conditions in the external environment, under which Vibrio cholerae can multiply in wastewater, sewers and reservoirs. Cholera outbreaks have been observed in pipeline accidents in which sewer water enters the water supply.

The mechanism of development of the disease in cholera

The entry gate of infection is the human gastrointestinal tract. At the same time, a significant part of the bacteria dies in the stomach, due to the action of hydrochloric acid. However, with reduced stomach acidity, bacteria survive and enter the small intestine, where the alkaline environment is favorable for their reproduction. Here, Vibrio cholerae actively secretes exotoxin - cholerogen. It leads to the reverse secretion of fluid and salts from the blood into the lumen of the small intestine, which leads to such disorders:

• decrease in circulating blood volume;
• thickening of the blood, which disrupts the functioning of the kidneys and develops acute renal failure;
• a decrease in the content of salts in the body, especially potassium and sodium, which leads to disturbances in the activity of the nervous system and heart rhythm;
• hypovolemic shock is an extremely serious condition associated with a critical decrease in free fluid and salts in the body, without adequate treatment can lead to death.

After the illness, an unstable and short-lived type-specific immunity to the cholera pathogen develops.

Clinical picture of cholera

The incubation period lasts from several hours to 5 days. Depends on the number of bacterial cells of vibrio cholerae that have entered the body. The most characteristic symptoms of infection are vomiting, diarrhea, and dehydration.

Features of vomiting, allowing to suspect cholera:

• occurs suddenly, without previous nausea;
• does not alleviate the patient's condition;
• vomiting of a large amount of odorless liquid and food residues (may be at the very beginning of the disease) - “vomiting a fountain”.

Also, diarrhea with cholera has distinctive features:

• diarrhea develops without abdominal pain (the main difference from other intestinal infections);
• there are no fecal stools (they can only be at the beginning of the disease), the stool is a clear, odorless liquid;
• on the 2-3rd day (sometimes on the 1st) of the disease, the stool acquires a characteristic appearance of "rice water" - a clear liquid with lumps of white mucus (dead cells of the epithelium of the mucous membrane of the small intestine).

Symptoms of dehydration in cholera are:

• decrease in turgor and elasticity of the skin - when collecting the skin into a fold, it straightens out within 0.5 - 1 minute (normal - immediately);
• "Laundress's hands" - wrinkling of the skin of the palms of the hands (occurs with laundresses when their hands are in the water for a long time);
• violations of the central nervous system (associated with the loss of salts) - manifested by a violation of consciousness, up to coma;
• a sharp decrease in diuresis - rare urination with a reduced amount of urine, while the urine is dark, concentrated.

There are several forms of cholera:

• typical form - the main symptoms are present - vomiting and diarrhea;
• atypical form - there may be no vomiting or diarrhea;
• erased form - characterized by one-time vomiting and diarrhea, dehydration does not develop, the infected person feels well, does not seek medical help (epidemiologically dangerous form);
• cholera algid - a severe variant of the course of cholera, after a few hours, continuous vomiting and diarrhea develop, dehydration, body temperature drops to 34-35 ° C, after a few days hypovolemic coma and death occur;
• lightning-fast form - several hours pass from the appearance of the first symptoms to the development of hypovolemic shock;
• dry form - there is a rapid development of dehydration, while vomiting and diarrhea are not expressed.

The severity of cholera depends on the degree of dehydration (dehydration) of the body:

1. I degree - dehydration is not expressed, water loss is 1-3% of body weight, there are no changes in the nervous system and heart;
2. II degree - water loss is 4-6% of body weight, there may be slight changes in the nervous system (irritability) and heart (arrhythmia);
3. III degree - 7-9% of body weight is lost of water, severe dehydration, confusion appears on the part of the nervous system, convulsions are possible, severe arrhythmia, the development of renal failure begins;
4. IV degree - very severe dehydration, water loss of more than 10% of body weight, consciousness is absent, hypovolemic coma develops, severe renal failure.

In children and the elderly, the course of cholera is more severe.

A complication of cholera can be cholera typhoid, which develops as a result of the penetration of other microorganisms from the intestine into the blood against the background of a decrease in immunity. Manifested by the fact that against the background of the symptoms of cholera, general intoxication joins with an increase in body temperature to 39-40 ° C, this significantly aggravates the course of cholera.

Diagnosis of cholera

The main methods are bacteriological and microscopic. With the bacteriological method of diagnosis, the material (vomit, feces, food debris, water) is collected in sterile dishes and inoculated on alkaline nutrient media. After the growth of cultures, biochemical and serological (using antibodies) identification of bacteria is carried out. The result is obtained in 24-48 hours. Material microscopy is an express method for diagnosing cholera. A positive result is considered when curved rod-shaped bacteria are detected, which are located in a smear in the form of a flock of fish.

Treatment

It is carried out only in the conditions of an infectious diseases hospital in compliance with anti-epidemic rules (thorough disinfection of feces and vomit, the work of medical personnel in anti-plague suits).

Unlike other infections, with cholera, pathogenetic therapy aimed at rehydration (restoration of lost fluid and salts) comes to the fore:

• oral rehydration - the patient drinks the proper amount of saline solutions (rehydron), oral rehydration is effective only in the absence of vomiting;
• intravenous rehydration - involves the intravenous administration of saline solutions containing salts of potassium, sodium, calcium, etc.

Rehydration is stopped only in the absence of vomiting and the predominance of urination over diarrhea for 12 hours.

The earlier measures are taken to restore the volume of fluid and salts in the body, the better the prognosis of the disease will be.

Etiotropic therapy is carried out to destroy the vibrio cholera in the patient's body. For this, antibiotics are used - doxycycline, less often ciprofloxacin or furazolidone (in case of resistance of the pathogen to doxycycline).

An extract from the hospital is carried out after the disappearance of the symptoms of cholera and 3 negative bacteriological results of the study of the material from the patient. Workers in the food industry and the water supply system are examined 5 times with an interval of 24 hours. After discharge, people who have had cholera are registered in the sanitary-epidemiological station and in the office of infectious diseases at the place of residence, where observation is carried out for 3 months. During the first month, a bacteriological examination of feces for the presence of cholera vibrio is carried out 1 time in 10 days.

cholera prevention

Includes non-specific prophylaxis and anti-epidemic measures, in case of detection of a patient or a bacteriocarrier.

Nonspecific prophylaxis of cholera is:

• personal hygiene rules - washing hands after visiting the restroom, before eating;
• you can’t drink water from unknown sources, especially from abandoned wells, reservoirs, but if it’s not possible, then you need to boil the water and add a little citric acid to it (cholera vibrio dies in an acidic environment).

Anti-epidemic measures are aimed at preventing the spread of cholera in the case of an identified patient or bacteriocarrier and include:

• hospitalization of a patient in a cholera hospital (deployed in an infectious diseases hospital);
• isolation and treatment of the patient in a separate box;
• placement of contacts (relatives, cohabitants of the patient) in a separate isolation ward with an observation period of 5 days;
• deployment of a provisional hospital, where patients with dyspeptic syndrome are observed until the diagnosis is fully established;
• contact people are given emergency prophylaxis of cholera, for which antibiotics (doxycycline) are used;
• carry out vaccination in the focus of the disease - corpuscular cholera vaccine and cholerogen-toxoid, immunity after vaccination persists for 4-6 months.

To limit and eliminate the source of cholera, the following measures are taken:

• restriction of entry and exit to an unfavorable territory;
• door-to-door rounds in order to identify patients;
• identification and isolation of people who have been in contact with cholera patients, as well as with contaminated environmental objects;
• current and final disinfection.

Since cholera is classified by the World Health Organization as a particularly dangerous infection, compliance with anti-epidemic rules is regulated in the country at the legislative level, so patients who refuse hospitalization and isolation are responsible.

It is important to remember that at the present stage, cholera is successfully treated, but only if you seek medical help early for adequate pathogenetic and etiotropic treatment.

Other especially dangerous infections.

And intoxication. During illness, a person loses up to 40 liters of fluid per day, which can lead to fatal dehydration. Every year, 3-5 million people fall ill with cholera, about 100-150 thousand of them die.

spread of cholera. Until 1817, only the inhabitants of India were ill with cholera, but then the disease spread beyond its borders. Today it is registered in 90 countries of the world. Despite all the efforts of doctors, cholera still cannot be defeated. In Africa, Latin America, Southeast Asia, there are constantly foci of the disease. This is due to the unsanitary conditions in which people live. There is a high risk of contracting cholera among tourists visiting Haiti, the Dominican Republic, Cuba, Martinique.

Most often, the disease flares up after social cataclysms, earthquakes or other natural disasters. When a large number of people are without drinking water. Waste water ends up in water bodies where people get water for cooking and where they wash. In such conditions, if one person becomes ill, others become infected. Therefore, cholera occurs in the form of epidemics, when up to 200 thousand people fall ill.

Exciter properties. Bacteria produce toxins that damage the lining of the small intestine. It is with the action of bacterial poisons that electrolyte imbalance and dehydration are associated.

Toxins secreted by Vibrio cholerae have the following properties:

• destroy the epithelium of the small intestine;
• cause copious excretion of water into the intestinal lumen. This fluid is excreted from the body in the form of bowel movements and vomiting.
• disrupt the absorption of sodium salts in the intestine, which leads to a violation of the water-salt balance and to convulsions.

The optimum temperature for the life of bacteria is 16-40 degrees. Best of all, cholera vibrio feels at a temperature of 36-37 ° C. Therefore, it actively develops in the human body and in shallow water bodies in tropical countries. It is resistant to low temperatures and does not die when frozen.

Vibrio cholerae dies when dried, exposed to sunlight, heated to 60 ° C and above, in contact with acids. Therefore, people with high acidity of gastric juice rarely get sick. Quickly dies when treated with acids and disinfectants.

The causative agent of cholera loves an alkaline environment. In the soil, on contaminated food and objects, Vibrio cholerae can live for several weeks. And in the water for several months.

Vibrio cholerae life cycle.

• Bacteria enter the human body with food and water.
• Some of them die in the stomach, but some overcome this barrier and end up in the small intestine.
• In this favorable alkaline environment, the vibrio attaches to the cells of the intestinal mucosa. It does not penetrate the cells, but remains on the surface.
• Vibrio cholerae multiply and release CTX toxin. This bacterial poison binds to the cell membranes of the small intestine and causes changes in their work. In the cells, the exchange of sodium and chlorine is disturbed, which leads to the release of a large amount of water and salt ions into the intestinal lumen.
• Dehydration of cells leads to disruption of communication between them and death. Dead cells of the mucosa are excreted from the body along with cholera vibrios.

Causes of cholera

Source of infection:

• sick person;
• a bacteriocarrier that secretes vibrio cholerae, but has no signs of disease.

In a sick person, feces and vomit are transparent and do not have a characteristic appearance and smell. Therefore, traces of contamination go unnoticed, which leads to the rapid spread of infection.

Mechanism of transmission of cholera fecal-oral - a sick person excretes bacteria during vomiting and diarrhea. Penetration into the body of a healthy person occurs through the mouth. It is impossible to catch cholera by airborne droplets.

Transmission routes:

• Water (basic) - through water contaminated with feces. In warm fresh and salt water bodies polluted by sewage, the concentration of bacteria is very high. People become infected by drinking water and while bathing. It is dangerous to wash dishes and products with such water.
• Contact-household - through objects, door handles, dishes, linen, contaminated with vomit or feces of the patient.
• Food - through oysters, mussels, shrimp, dairy products, fruits, fish and meat dishes that have not undergone heat treatment. Bacteria get to products with dirty water, from carriers or by means of flies.

Cholera Risks

• Bathing in polluted reservoirs, washing dishes in them, drinking water.
• Eating seafood, especially raw shellfish.
• Visiting countries with a low standard of living, where there is no running water and sewerage, sanitary standards are not observed.
• Large refugee camps with poor sanitation and no safe drinking water.
• Wars, social cataclysms, when there is a shortage of drinking water.
• At risk are people suffering from gastritis with low acidity and achilia (a condition in which there is no hydrochloric acid in the gastric juice).

cholera prevention

What to do if the risk of developing cholera is high?

In order to stop the spread of cholera, it is very important to isolate the sick person in time, observing the appropriate precautions. This avoids infection of healthy people. The State Committee for Sanitary and Epidemiological Supervision has developed a special instruction in case of a high risk of developing cholera.

1. All patients with cholera and bacteria carriers are isolated in a special hospital or isolation ward. They are prescribed after the disappearance of the symptoms of the disease and three bacteriological studies with an interval of 1-2 days. Tests should confirm that there are no bacteria in the intestines.
2. They identify everyone with whom the patient has been in contact, take tests three times and carry out chemoprophylaxis - a short course of antibiotics. Those who were in close contact are isolated in special boxes.
3. Disinfection is carried out in the room where the patient was and at his workplace. To do this, a disinfection team is called from the center of the State Committee for Sanitary and Epidemiological Supervision. Disinfection is carried out no later than 3 hours after hospitalization of the patient.
4. The disinfection team puts on an anti-plague suit (overalls) of the 2nd type with oilcloth oversleeves and an apron, a hood, and a respirator.
5. Disinfectants disinfect the floor and walls of the premises to a height of 2 meters. To do this, use: chloramine 1%, sulfochloranthin 0.1-0.2%, lysol 3-5%, perhydrol.
6. Clothes, bedding, carpets and other soft items are packed in bags and sent for disinfection in a disinfection chamber. The dishes are soaked in a 0.5% solution of chloramine for 30 minutes.
7. In the department, the patient is given an individual bedpan, which after each use is soaked in a disinfectant solution: 1% chloramine for 30 minutes or 0.2% sulfochloranthin for 60 minutes.
8. In the hospital, clothes, dishes and bedding are disinfected by boiling for 5-10 minutes or immersed in a 0.2% solution of sulfochlorantin for 60 minutes.
9. At least 2 times a day in the room where the patient is located, cleaning is carried out using disinfection solutions of 1% chloramine, 1% sodium hypochlorite.
10. The remains of food and excretion of the patient are covered with bleach in a ratio of 1:5.
11. The medical staff caring for a cholera patient is wearing a type IV suit - a jumpsuit with a hood. When taking tests and processing patients, rubber gloves, oilcloth (polyethylene) apron, rubber shoes and a mask are added.

What to do if there was or is contact with a cholera patient?

Those who had close contact with the patient (living together) are isolated in special boxes for 5 days. During this period, a three-fold examination of the contents of the intestine is carried out.

The rest of the contacts are observed on an outpatient basis: within 5 days they come for an examination and take tests.
For emergency prophylaxis, when contact with a patient or carrier has taken place, one of the antibiotics is used.

A drug	Multiplicity of reception	Duration of treatment
Tetracycline	1.0 g 2-3 times a day	4 days
Doxycycline	0.1 g 1-2 times a day	4 days
Levomycetin	0.5 g 4 times a day	4 days
Erythromycin	0.5 g 4 times a day	4 days
Furazolidone (with intolerance to antibiotics)	0.1 g 4 times a day	4 days

People who have been in contact with the patient do not need to observe special hygiene measures. It is enough to take a shower once a day and wash your hands thoroughly after each visit to the toilet.

Cholera vaccination

The World Health Organization recommends the use oral vaccines during disease outbreaks. Drugs that are injected under the skin are not recommended by WHO experts due to unproven efficacy.

The vaccine is not a universal remedy. It is just an addition to other anti-epidemic measures (isolation of patients, identification and treatment of contacts and carriers, exclusion of the spread of bacteria, preventive treatment, disinfection).

Vaccine Dukoral (WC-rbs)

Vaccine from formalin and heat-killed Vibrio cholerae and their toxin. The vaccine is used with a buffer solution to protect the drug from the effects of stomach acid. Administer 2 doses of the vaccine 7 days apart. Dukoral provides 85-90% protection for 6 months. Over time, the effectiveness of the vaccine weakens - after 3 years it is only 50%. Applicable from 2 years of age.

Shanchol and mORCVAX oral cholera vaccines

Vaccines from killed vibrio cholerae of two serogroups without toxin components. Bacteria trigger protective reactions, leading to the appearance of a strong immunity that protects against the disease for 2 years. The vaccination consists of 3 doses given 14 days apart. The effectiveness of vaccines is 67%. The vaccine can be given to children as young as one year of age.
Studies have shown the safety and effectiveness of these vaccines.

Vaccine CVD 103-hgr from live attenuated vibrio cholerae has been discontinued.

Who is vaccinated for:

• refugees in overcrowded camps;
• residents of urban slums;
• children in high-risk areas;
• individuals who travel to regions with a high risk of cholera.

Tourists do not need to be vaccinated.

Symptoms and signs of cholera

incubation period of cholera. From the moment of infection to the onset of symptoms, it takes from several hours to 5 days. Most often 1-2 days.

The course of cholera. The disease can occur in different forms, depending on the characteristics of the body. In some people, these are erased forms with a slight indigestion. Others lose up to 40 liters of fluid during the first day, which leads to death. Children and the elderly are more susceptible to cholera than others.

There are 4 degrees of dehydration of the body and the corresponding degrees of the course of the disease:

• I - fluid loss is 1-3% of body weight - mild cholera, observed in 50-60% of cases;
• II - fluid loss 4-6% - moderate;
• III - fluid loss 7-9% - severe course;
• IV - fluid loss of 10% of body weight or more - very severe, 10% of cases.

The disease always begins against the background of full health. The temperature is usually not elevated, and when dehydrated, it drops below 36 degrees. The duration of the disease is 1-5 days.

Symptoms of cholera

Symptom	External signs	The mechanism of development of this symptom	The timing of the onset and disappearance of this symptom
Diarrhea (diarrhea)	The stool is liquid at first. Then the discharge takes the form of "rice water": a clear, odorless liquid with white flakes. If the intestinal mucosa is severely damaged, then a slight admixture of blood appears and the stools look like "meat slops". The urge to defecate is almost impossible to contain. Depending on the degree of dehydration, stools from 3 to 10 or more times a day. Abdominal pain does not occur. There may be slight soreness near the navel and a slight rumbling.	Vibrio cholerae toxin causes swelling of the intestinal mucosa. Then the cells begin to secrete large amounts of water and electrolytes.	Diarrhea occurs from the first hours of illness. If the bowel movements become fecal in nature, this indicates an improvement.
Vomit	Vomiting the first time the contents of the stomach. In the future, profuse vomiting of a watery liquid without color and odor. Vomiting 2 to 20 or more times. Nausea does not occur. Vomiting practically does not cause tension in the muscles of the stomach and abdominals.	Fluid secreted in the small intestine travels up the gastrointestinal tract.	Vomiting occurs 3-5 hours after the onset of the disease.
Thirst	With 1-3 degrees of dehydration, thirst is strongly expressed. At the 4th degree, patients cannot drink because of severe weakness.	The loss of a large amount of fluid causes a feeling of dryness in the mouth and thirst.	throughout the illness.
Urine	The amount of urine decreases and it darkens.	The more the body loses fluids, the less urine is produced and the higher its concentration. With severe dehydration, patients stop urinating.	on the second day of illness. Normalization of urination indicates that the treatment is effective and the patient's condition is improving.
Dryness of the mucous membranes of the mouth and eyes	Decrease in the amount of saliva produced. Dry cracked tongue. Hoarseness of voice is the result of dryness of the mucous membranes of the pharynx. Eyes sunken, almost no tears stand out	Dehydration leads to dry skin and mucous membranes. The work of all glands of external secretion slows down.	10-15 hours after the onset of the disease.
convulsions	The calf muscles, the hands of the feet, the muscles of the face. With severe dehydration of 3 and 4 degrees, convulsions of all skeletal muscles. They are excruciating and painful.	Spasmodic muscle contraction is associated with potassium deficiency, which is caused by diarrhea and vomiting.	From the 1st day of illness until the condition improves.
Pulse	Frequent pulse of weak filling.	The loss of fluid and bases leads to thickening of the blood, a decrease in its volume, an increase in its acidity - acidosis develops. The heart, by increasing the rate of contractions, tries to provide the body with oxygen.	With dehydration of 2-4 degrees. The pulse returns to normal after the restoration of the water-salt balance.
Increased breathing	Breathing is frequent and shallow.	The change in respiratory rate is associated with the effect of acids on the nervous system and on the respiratory center in the brain.	Appears with dehydration of the 2nd degree a few hours after the onset of the disease.
Turgor (elasticity) of the skin	The skin is dry, pale, in severe cases cyanotic. Cold to the touch. Its elasticity is reduced. If you squeeze the skin fold with two fingers, hold for 2 seconds and release, it will take time for the skin to even out.	The reason is dehydration of the skin. In the cells themselves and in the intercellular space, the number of water molecules decreases.	Appears 6-8 hours after the onset of the disease. Disappears after restoration of water-salt balance.
General state	Drowsiness, lethargy, irritability	A breakdown is a sign of dehydration of the nervous system and poisoning of the body with toxins.	From the first hours of illness to recovery.

Diagnosis of cholera

Diagnosis of cholera is based on examination of the patient and the presence of characteristic symptoms (vomiting after diarrhea, dehydration). It is taken into account whether a person could become infected with cholera. Due to the nature of the disease, there is no need for instrumental diagnostics. The diagnosis is confirmed by laboratory diagnostic methods.

For the diagnosis of cholera, the material is examined:

• excreta;
• vomit;
• water from suspected contaminated water bodies;
• foodstuffs that may have been contaminated;
• swabs from household items and the environment;
• intestinal contents in contacts and carriers;
• in those who died of cholera, fragments of the small intestine and gallbladder.

Laboratory methods for diagnosing cholera

Diagnostic method	How is it made	What are the signs of cholera
Microscopy of the material under study	A small amount of the test material is applied to a glass slide. Stained with aniline dyes according to the Gram method and studied under a microscope.	A large number of curved rods with one flagellum. Vibrio cholerae is a gram-negative bacterium, so it does not stain strongly with aniline dyes. Has a pink color.
Bacteriological examination - sowing on nutrient media.	The test material is inoculated on nutrient media: alkaline peptone water or nutrient agar. For reproduction of cholera vibrio, the environment is placed in a thermostat. At a temperature of 37 degrees, optimal conditions are created for the growth of bacteria.	A film of bacteria forms on liquid media. They are studied under a microscope. Live cholera vibrios are very mobile. In a drop of liquid, they swim like a flock of fish. On a thick medium, the bacteria form round bluish transparent colonies.
Agglutination reaction with anti-cholera O-serum	Bacteria grown on media are diluted in test tubes with peptone water. Anti-cholera serum is added to one of them. The tube is placed in a thermostat for 3-4 hours. To determine the type of cholera vibrio, there are sera that cause gluing and precipitation of only one type of vibrio Inaba and Ogawa. Each of these species sera is added to one of the test tubes with vibrio cholerae.	Serum causes agglutination only of cholera vibrios. The bacteria stick together and precipitate as white flakes. A positive result proves that the disease is caused by this particular pathogen, and not by another cholera-like vibrio.
Accelerated diagnostic methods take 25-30 minutes
Lysis (dissolution) by cholera bacteriophages - viruses that infect only vibrio cholerae.	Bacteriophages are added to a test tube with peptone water. The liquid is stirred. Then its drop is studied under a microscope.	Viruses infect bacteria and after 5-10 minutes cholera vibrios lose their mobility.
Agglutination of chicken erythrocytes	Chicken erythrocytes 2.5% are added to peptone water with a high content of the cholera pathogen.	Vibrio cholerae cause red blood cells to stick together. A precipitate in the form of reddish-brown flakes falls to the bottom of the test tube.
Hemolysis (destruction) of sheep erythrocytes	Sheep erythrocytes are added to a test tube with a suspension of bacteria. The drug is placed in a thermostat for 24 hours. Vibrio cholerae causes the destruction of blood cells.	The solution in the test tube becomes homogeneous and turns yellow.
Immunofluorescence method	A preparation is prepared from the material grown on nutrient media. It is treated with anti-cholera serum, which causes the luminescence of vibrio cholerae and examined under a fluorescent microscope.	Under a microscope, Vibrio cholerae glow with a yellow-green light.
Vibrio immobilization method after treatment with specific cholera 01-serum	A drop of material (feces or vomit) is applied to a glass slide. A drop of diluted anti-cholera serum is also added there. Cover with a second glass and examine under a microscope.	Some of the bacteria stick together, forming small clusters that move slowly. Individual cholera vibrios retain their mobility.

cholera treatment

Hospitalization of patients. Treatment of patients with cholera is carried out only in the infectious diseases department of the hospital in an isolated box. If there are many patients, a cholera hospital is organized.

Regime in the treatment of cholera. The patient needs bed rest for the entire period of illness, while there are clinical manifestations: nausea, vomiting, weakness. It is advisable to use a Philips bed with a hole in the buttocks area. It is also equipped with a scale to monitor fluid loss and a container to collect feces, urine and other secretions. Everything is collected in a measuring bucket. Every 2 hours, the medical staff evaluates the amount of fluid that the patient is losing. Based on this, it is calculated how much saline solutions must be administered in order to prevent dehydration.
Physiotherapy, massage and physiotherapy exercises are not used in the treatment of cholera.

Diet for cholera. There are no special dietary restrictions. In the first days of the disease, diet No. 4 is prescribed. It is indicated for diseases of the intestines, accompanied by severe diarrhea. These are liquid, semi-liquid and pureed dishes, boiled or steamed.

Forbidden:

• soups on strong meat and fish broths, milk soups
• fresh bread and flour products
• fatty meats and fish, sausages, canned food
• whole milk and dairy products
• legumes, millet, barley and pearl barley, pasta
• raw vegetables and fruits, dried fruits
• sweets, honey, jam
• coffee, carbonated drinks

Recommended:

• soups on fat-free broth with the addition of steam quenelles and meatballs, egg flakes. Mucous decoctions of cereals
• cereals on the water from semolina, mashed rice, oatmeal, buckwheat
• premium wheat bread crumbs
• boiled meat soufflé, steamed meatballs, dumplings, meatballs. Use low-fat varieties of meat: rabbits, chickens, turkeys, beef, veal
• fresh calcined or unleavened grated cottage cheese in the form of a steam soufflé
• 1-2 eggs per day in the form of an omelette or soft-boiled
• tea, decoction of wild rose, dried blueberries, currants, quince

Such a strict diet is prescribed for 3-4 days until the stool normalizes. Then they switch to diet number 15. It does not have strict restrictions.

Forbidden:

• fatty meats
• spicy seasonings
• smoked meats

After an illness, foods containing potassium are needed: jacket potatoes, dried apricots, black currants, grapes. Potassium reserves are replenished in the body slowly. Therefore, these products must be consumed within 2 months.

Drug therapy for cholera

Restoration of water-salt balance must be carried out from the first hours of the disease. It is important that the body receives more fluid than it loses.

Water-salt solution drink or enter into the stomach with a nasogastric tube with dehydration of 1-2 degrees. Solution components:

• drinking water heated to 40 degrees - 1 l;
• sodium bicarbonate (baking soda) - 2.5 g;
• sodium chloride (table salt) - 3.5 g;
• potassium chloride - 1.5 g;
• glucose or sugar - 20 g.

You can use ready-made preparations Glucosolan, Regidron, one glass every 10 minutes, for 3 hours. Further, the solution must be drunk constantly, in small sips throughout the day.

Saline solutions necessary for 3 and 4 degrees of dehydration. The first 2 hours they are administered intravenously by stream, then drip. Use preparations Chlosol, Kvartosol or Trisol. They make up for the lack of water and minerals.

antibiotics for cholera. To combat cholera vibrio, one of the drugs is prescribed.

Nitrofurans. Furazolidone is an antimicrobial and antibacterial agent. It is taken at 100 mg every 6 hours for antibiotic intolerance.

The duration of treatment depends on the severity of the course of cholera and is 3-5 days. After an illness, a person has a strong immunity.

Dispensary observation over the ill set for 3 months. In the first month, it is necessary to take tests 1 time in 10 days. In the future, 1 time per month.

Folk methods of treatment of cholera.

Since cholera is a particularly dangerous infection and can cause death during the first day, self-medication in this case is unacceptable. Alternative methods can be used as an addition to the main therapy.

Warming. Since the patient's body temperature decreases, it must be warmed. For this person they cover with heating pads. The temperature in the room is not lower than 25 degrees.

Periwinkle used to combat diarrhea and disinfect the intestines. To prepare tea, 1 teaspoon of dried raw materials is brewed with a glass of boiling water. After cooling, the tea is filtered. Use 100 ml 3 times a day.

Red wine contains a lot of tannin, which stops the growth and reproduction of cholera vibrio. Its dry wine is recommended to drink 50 ml every half an hour.

Herbal tea from chamomile, wormwood and mint. Herbs are mixed in equal proportions. To make tea, use 5 tablespoons of the mixture per liter of boiling water. Drink 2 liters a day in small portions. This remedy has an antimicrobial effect and relieves intestinal spasms.

Malt. Add 4 tablespoons of malt per liter of water. Boil for 5 minutes. Let it brew, filter, add 2 tsp. Sahara. This drink contains many minerals and biologically active substances.

Therefore, it was previously used to replenish fluids and salts.

In conclusion, we recall that it is not difficult to protect yourself from cholera. Just wash your hands and use clean water.

Follow the rules of hygiene and be healthy!

cholera clinic. The incubation period lasts from 6 hours to 6 days. Cholera begins with diarrhea. The urge to defecate appears suddenly, usually painlessly. The stools are initially fecal in nature, and subsequently acquire a liquid character, may resemble rice water; odorless, but sometimes there is a peculiar smell of dampness, fish. The patient feels weakness, moderate thirst, dry mouth.

Perhaps rumbling at the navel or lower abdomen. Physical and chemical parameters of blood remain normal. Within 1-2 days, often spontaneously, recovery occurs. The above clinical symptoms correspond to patients with dehydration of the 1st degree (cholera enteritis), appear in 40-60% of cholera patients and are recorded more often during the height and recession of an epidemic outbreak. Fluid loss is from 1 to 3% of body weight.

Stage 2 is dehydration with fluid loss from 4 to 6% of body weight. After a few hours or a day, repeated vomiting joins the diarrhea, sometimes with a fountain, without nausea (cholera gastroenteritis develops). Vomit quickly loses its characteristic appearance, becomes watery and also resembles rice water. Profuse diarrhea develops with a frequency of stools up to 15-20 times a day, which lose their fecal character.

Dehydration sets in quickly. Patients complain of weakness, dry mouth, thirst, dizziness. The skin is dry, pale, often with unstable cyanosis, hoarseness of the voice, sometimes spasms of the calf muscles. Skin turgor becomes reduced (the fold straightens slowly). Facial features are sometimes pointed, shadows under the eyes. Blood pressure is lowered (100 mm Hg and below), diastolic is not lower than 40 mm, moderate tachycardia (up to 100 in 1 min.). Possible transient oliguria

3 degree of dehydration corresponds to fluid loss from 7 to 9% of body weight. The onset of the disease is acute, with a rapid increase in symptoms, repeated vomiting, very frequent bowel movements, sometimes in the form of "rice water", significant thirst, constant dizziness, fainting, severe weakness, the temperature is often normal. There are tonic convulsions.

These symptoms are supplemented by acrocyanosis, a decrease in skin turgor (the fold straightens slowly). The features of the patient's face are sharpened, the eyes sink, dark circles appear under the eyes (a symptom of "dark glasses"), the look is suffering, the voice is hoarse, sometimes only a whisper. Increases hypovolemia, hypoxia, thickening of the blood leads to hemodynamic disorders.

The patient's behavior becomes restless (fear of death), sometimes there is excitement. BP goes down. Systolic pressure is 80-60 mm Hg. Art., diastolic pressure may not be determined, the pulse is weak, thready, 120-130 or more beats per 1 minute. Mucous membranes are dry, tachypnea (up to 30 or more in 1 minute), oliguria, often anuria.

The mass of circulating blood plasma decreases to 33 ml/kg, extrarenal azotemia increases. Neutrophilic leukocytosis is observed in the blood, ESR is accelerated. At this stage, the clinical symptoms correspond to manifestations of hypovolemic shock.

Dehydration of the 4th degree, or cholera algid, is decompensated dehydration with fluid loss of up to 10% or more of body weight. This form is observed during outbreaks of cholera in 8-15% of patients. The patient's condition deteriorates sharply. All symptoms of dehydration are markedly pronounced. Hypovolemic shock progresses. Due to intestinal paresis, diarrhea and vomiting may temporarily decrease or even stop, but sometimes they resume against the background of rehydration or after it has ended.

Due to severe hemodynamic disturbances and spasm of peripheral vessels in patients with cholera, coldness of the extremities and skin of the trunk occurs. The skin is not only cold, but sometimes covered with sticky sweat. Body temperature drops to 35 degrees or to 31 degrees (“cadaveric temperature”).

The skin is pale, gray; acquires a marble pattern, loses its elasticity, wrinkles, does not straighten out when assembled into a fold; wrinkles appear on the palms ("the laundress's hand"). The facial features are sharpened, the eyes sink (facies cholerica), the lips, the tip of the nose, the auricles become cyanotic. In some areas (back, buttocks, if the patient is lying on his back), bluish spots appear (due to blood metastases).

The tongue is dry, covered with a grayish coating. The mucous membranes of the oral cavity are dry. The voice is quiet, up to complete aphonia, due to dryness and non-closure of the vocal cords, their convulsive contraction. The expressed tachycardia, pulse on peripheral vessels and the ABP are not defined. Pericardial friction rub is detected. The patient is in deep prostration.

Breathing is shallow, frequent, uneven. Dehydration, hypokalemia, acidosis can cause seizures. Convulsions of a tonic nature extend to all pectoral muscles, including the diaphragm, which leads to hiccups. There may be generalized convulsions - opisthotonus (as in patients with tetanus). The severity of tachycardia, shortness of breath, and a drop in blood pressure correlate with the degree of dehydration and metabolic disorders.

If timely treatment is not carried out, a phase of asphyxia sets in, cholera coma and death against the background of loss of consciousness, severe hemodynamic disturbances, convulsions.

The reactive period (recovery) in patients with cholera can occur against the background of dehydration of any degree, including algida. This period is characterized by a gradual extinction of the acute manifestations of the disease, the patient's skin acquires a normal color, warms up, the pulse approaches normal, blood pressure rises, the voice becomes stronger, urine appears to polyuria; within 2-3 days the body temperature returns to normal. Such reverse changes in most cases occur during intensive care.

Atypical forms of cholera.

Among these forms, severe is fulminant (fulminant), when all its clinical manifestations increase so rapidly that only a few hours pass from the moment the first symptoms appear to hypovolemic shock and death.

Dry cholera.

This is a form when death occurs in the presence of phenomena of circulatory and respiratory failure without diarrhea and vomiting. Clinical manifestations are characteristic of hypovolemic shock, the intestines are filled with fluid, but diarrhea does not have time to develop due to the rapid onset of intestinal paresis and circulatory disorders. This course is very difficult to diagnose, it is observed in very weakened, emaciated individuals.

Hemorrhagic cholera.

It can be with some somatic diseases of the liver, blood vessels, digestive tract (peptic ulcer, ulcerative colitis) when blood impurities appear in the feces and vomit (stools look like meat slops). This gives reason to some clinicians to distinguish hemorrhagic cholera as a special variant of the course of cholera. Similar manifestations can be with mixed infection (cholera + shigellosis). The severity of the course of the disease is affected by dysbacteriosis, chronic alcoholism, diabetes mellitus and others.

Erased cholera.

Vibrio cholerae can also be detected in individuals who did not have bowel dysfunction (“asymptomatic vibrio carriers”). But an increase in their sera of vibriocidal antibodies testifies more in favor of a subclinical (erased) infection.

Vibrio carrying.

Clinical recovery in time does not always coincide with the cleansing of the body from the pathogen. Sometimes this process can be delayed for 2-3 weeks, which necessitates dispensary monitoring of people who have been ill (carriers are convalescents).

There are cases of infection with Vibrio cholerae of the gallbladder, which requires duodenal sounding followed by bacteriological examination of bile.

A particularly severe course is observed in children and the elderly, in which the mortality rate reaches 20-40% or more.

Features of the modern course of cholera associated with the specificity of the vibrio El Tor. Cholera caused by this pathogen has a predominantly milder course. Erased and atypical forms with prolonged post-infectious or healthy vibrio carrying are more often observed.

Complications.

They can occur at different stages of the disease, but with the rapid course of cholera, they cannot always be recognized in time. Hypovolemic shock is often considered not as a complication, but as a variant of the severe course of cholera - this is the main criterion for severity.

Acute renal failure occurs in the presence of 3-4 degrees of dehydration, especially against the background of irrational therapy. Long-term infusion therapy, carried out by puncture of the veins of the cubital or veins of the leg, can lead to the formation of phlebitis, pyrogenic reactions, hypostatic pneumonia, and the like.

The content of the article

Cholera(synonyms of the disease: cholera asiatica, cholera El-Top) is an acute, especially dangerous infectious disease that is caused by cholera vibrios, has a fecal-oral infection mechanism, characterized by epidemic spread and a clinical picture of severe gastroenteritis with severe dehydration, hemodynamic disorders.

Historical data for cholera

Cholera is one of the oldest human diseases. Its name is believed to come from the Greek cholero - gutter, gutter. There are four periods in the history of cholera. The first period of the spread of cholera lasted from ancient times until 1817. It was at that time that cholera was an endemic disease for the countries of Southeast Asia located in the basin of the Ganges and Brahmaputra rivers. In 1817, cholera spread beyond India, to the Philippines, to China, Japan, regions of North and East Africa, and later through the southern regions of Russia, Transcaucasia to European countries, in particular to the territory of modern Ukraine. During the second period in the history of cholera (1817-1926 pp.) there were six devastating cholera pandemics (1817-1823, 1826-1837, 1846-1862, 1864-1875, 1883-1896, 1902-1925 pp.).

For the first time, cholera vibrio, as a probable causative agent of the disease, was described in 1849 p. Poucliet, in 1853 p. Pacini and in 1874 p. E. Nedzvedskaya. However, only in 1883, at the beginning of the fifth pandemic, R. Koch isolated Vibrio cholerae in pure culture and described its properties. In 1906 p. F. Gotschlich at the El-Top quarantine station isolated another biological variant of the vibrio, which differed from the "classical" one in its ability to hemolyze sheep erythrocytes. This vibrio was known before as the causative agent of cholera-like diseases, but it was not recognized as the causative agent of cholera.

In the third period of the history of cholera (1926-1960 pp.) It was again observed in the endemic regions of Southeast Asia (India, Pakistan, Bangladesh). In 1937-1939 pp. On the island of Celebes (Sulawesi) in Indonesia, there was an outbreak of "cholera-like" diseases with a high (70%) mortality rate, which was caused by El Top vibrio. Since 1961, this disease has spread to other countries. Since 1961, the fourth period of the spread of cholera began (the seventh pandemic), which continues to this day. By decision of WHO (1962), the El-Top vibrio is officially recognized as the causative agent of cholera. The seventh cholera pandemic caused by this pathogen is characterized by some clinical and epidemiological features. In the 1970s and 1980s, the pandemic reached the countries of Europe (including those observed in southern Ukraine) and Africa. Since 1970, cholera has been reported annually in 40 countries around the world. According to incomplete WHO data, for the period from 1961 to 1984 pp. 1.5 million people worldwide have been ill with cholera. Most of all cholera cases occurred in African countries, where stable endemic foci formed in some regions. In recent years, the incidence of cholera remains quite high. The epidemic situation was especially dangerous in the early 1990s in the countries of Latin America. In the same years, cholera was registered in India, Australia, USA, England. France, Spain, Romania, Ukraine. It is alarming that, along with cholera El-Top, cases of the disease caused by the classic biovar of cholera vibrio have become more frequent.

Etiology of cholera

The causative agents of cholera are the biovars Vibrio cholerae: Vibrio choleare asiaticae and Vibrio El-Tor from the genus Vibrio, family Vibrionaceae. Vibrios cholerae have the form of a curved stick-comma 1.5-3 microns long, 0.2-0.3 microns thick; very mobile, monotrichous, not forming spores and capsules, gram-negative. They grow well on simple alkaline media at temperatures from 10 to 40 ° C. On dense nutrient media they form transparent, blue-tinted, convex, disc-shaped colonies. Vibrio cholerae ferment disaccharides in different ways. According to the ability to ferment sucrose, arabinose, mannose, Heiberg divided all vibrios into 8 chemovars, vibrio cholerae belong to the 1st chemovar: sucrose (+), arabinose (-), mannose (+).

Vibrio cholerae are able to produce thermostable endotoxin, thermolabile exotoxin (cholerogen) with a strong enterotoxic effect, as well as fibrinolysin, hyaluronidase, collagenase, neuraminidase and other enzymes. The causative agents of cholera have a type-specific thermostable O-antigen and a group thermolabile H-antigen (Basal). According to O-antigens, cholera vibrios are divided into 3 serological types: Otava, Inaba and Gikoshima. In relation to cholera phages, vibrios are divided into 5 main phage types: A, B, C, D, E.

In patients with acute intestinal infections, vibrio carriers, as well as from wastewater from open reservoirs, NAG vibrios (non-agglutinable) are isolated, which are not agglutinated by polyvalent cholera O-serum, do not differ in morphological, cultural and enzymatic properties from cholera vibrios, have the same H -antigen, but belong to different O-groups. Recent studies call for a reconsideration of the nature of NAG-vibrio. It is likely that the phenomenon of non-agglutinability is a temporarily acquired feature of any biovar of cholera vibrios as a result of their long stay and reproduction under adverse environmental conditions. It is believed that upon returning to favorable conditions, these vibrios are able to renew their previous (including pathogenic) properties.

Vibrio cholerae are relatively resistant to environmental factors, especially El-Top biovar. They remain viable for a long time in water, soil, sewage, beach sand, sea water, on food (for 1-4 months), in faeces without drying out - up to 2 years. Under certain conditions, they can breed even in water bodies, silt. All vibrios are not resistant to direct sunlight, drying. At a temperature of 80 ° C, they die within 5 minutes, they are very sensitive to the action of disinfectants.

An important feature of all vibrios is their high sensitivity to acids. So, chlorocarbon (hydrochloric) acid, even diluted 1: 10,000, has a detrimental effect on them.

Epidemiology of cholera

Cholera is a typical anthroponosis. The source of infection are sick people and bacteria carriers. Patients excrete the pathogen with feces and vomit in any period of the disease; 1 ml of liquid feces contains 107-110 vibrios. However, more epidemiologically dangerous are patients with a mild, erased form of cholera, and "healthy" carriers, contacts with which are not limited. Convalescents and vibrio carriers after an illness caused by a classic pathogen biovar can excrete vibrios from 2-3 weeks to 2 months (rarely up to 1-2 years).

Carriage of vibrio El Gor lasts 5-7 years. On average, carriage among convalescents with El-Top cholera is 30-50%, while with classical cholera it does not exceed 20%. In the focus of cholera, the ratio of patients to carriers is 1: 10-20, and in El Top cholera it is 1: 20-40. The mechanism of infection of cholera is fecal-oral, the pathogen enters the body most often through water, less often through food or contact-household.
Recently, due to the intensification of urbanization processes, as well as due to the lag in the development of the social sphere, the lack of proper wastewater treatment, massive pollution of open water bodies has been observed. An analysis of the epidemiological situation of cholera in Ukraine indicates a significant proportion of the water factor in the spread of this infection. It is alarming that on the territory of some eastern and southern regions of Ukraine there is a constant presence of El-Top vibrio in open water, resulting in a water outbreak of cholera in the Odessa region in 1991. In 1990 - 1991 pp. isolated cases of cholera were recorded in Berdyansk, Mariupol, also caused by the use of infected water from open reservoirs. A special role belongs to hydrobionts as objects of infection transmission. So, in fish, crabs, shrimps, molluscs, when they are in polluted water bodies, El-Top vibrios accumulate and persist for a long time. Less commonly, direct infection occurs through contact with a patient or a vibrio carrier. Recent outbreaks of cholera caused by consumption of infected vegetables, fruits, milk, etc.

Susceptibility to cholera is high. The most susceptible persons with hypo-, anacid state of gastric secretion. In endemic regions, diseases predominate among children and the elderly. At the beginning of the epidemic, men aged 20-40 are more likely to get sick.

Seasonality summer-autumn, which is associated with more favorable conditions for the storage and reproduction of the pathogen in the external environment, the activation of transmission factors, an increase in the consumption of foods that have an alkaline reaction (vegetables, fruits), as well as an increase in the consumption of water, various drinks, as a result of which the acidity of the stomach contents decreases, which promotes the passage of vibrios into the small intestine.

The transferred disease leaves rather stable species-specific immunity. Recurrences are rare. Such features of El-Top cholera as more frequent and prolonged carriage, greater resistance of the pathogen to environmental factors and antibiotics, cause a more serious epidemiological prognosis.

Pathogenesis and pathomorphology of cholera

The entrance gate of infection is the alimentary canal. A prerequisite for the introduction of the pathogen into the small intestine is to overcome the acid barrier of the stomach. The vibrios that have overcome it enter the small intestine, where, due to the alkaline reaction of the contents, favorable conditions are created for their reproduction. In the small intestine, vibrios release toxic substances. Cholerogen (exotoxin), which by its nature is a pharmacological poison, and not an inflammatory agent, binds to specific enterocyte receptors, penetrates into cells, disrupts their metabolism, Vibrio cholerae toxins activate the synthesis and release of a kind of hormone - vasoactive intestinal peptide (Whiggy). All this activates the enzymes adenylcyclase and guanidine cyclase. As a result, the synthesis of cyclic adenosine monophosphate (cAMP) and guanidine monophosphate (cGMP) increases, the level and intensity of secretion in the intestine increases significantly. The consequence of these processes is the activation of the transport of isotonic fluid into the intestinal lumen with a simultaneous violation of its reabsorption due to the blockade of the sodium pump. The reabsorption deficit can reach 1 l/h or more. Diarrhea occurs, followed by vomiting. The liquid secreted from the intestines, rich in sodium, potassium, chlorine ions. The loss of isotonic fluid with faeces and vomiting reaches 20 liters or more, which, as a rule, is not observed in intestinal infections of other etiologies. All these phenomena cause catastrophic isotonic dehydration, hypohydremia, thickening of the blood, dehydration of the body, electrolyte imbalance, hypergyroteinemia, which impairs the blood supply to tissues, which leads to hypoxia, acidosis, extrarenal azotemia. In the final phase of the process, the patient may die on the background of hypovolemic shock, thrombohemorrhagic syndrome, extrarenal urination disorders, cholera coma.

The scheme of the pathogenesis of cholera has the following stages:

1. The entry of cholera vibrio into the intestine, its reproduction in an alkaline environment and the destruction, release and accumulation of toxins, including cholerogen.
2. Increased secretion of isotonic fluid:
   a) activation of the cholerogen adenylcyclase of enterocyte membranes, increased formation of cAMP (cGMP), increased permeability of biological membranes of enterocytes for sodium and water,
   b) blocking the sodium pump, a sharp decrease in the reabsorption of isotonic fluid.
3. Dehydration (in a catastrophic form).
4. Thickening of the blood, slowing of blood flow, hypoxemia, hypoxia.
5. Metabolic acidosis with accumulation of toxic products.
6. Extrarenal urination disorders (hypohydremia) up to anuria, in severe cases - extrarenal coma.

When examining the corpse, the skin color is earthy-cyanotic, the cadaveric spots are purple-violet. It turns out the accumulation of blood in the main vessels. Blood during venesection does not follow, it has a jelly consistency. The intestines are filled with a liquid that resembles cloudy rice water. All researchers pay attention to the absence of inflammatory changes, the mucosa of the small intestine is almost unchanged, covered with a delicate pityriasis. During microscopic examination, necrosis and desquamation of the epithelium of the villi of the small intestine are not detected, its structure is preserved. In the myocardium and liver, dystrophic changes are observed, in the kidneys - fatty and vacuolar degeneration of the nephron tubules. Due to impaired blood supply, the kidneys are reduced, the capsule is easily removed from them. Pleura, pericardium, peritoneum covered with sticky viscous liquid.

cholera clinic

The incubation period lasts from several hours to five days (usually 1-3 days). Prodromal phenomena are atypical, but sometimes within a short period (from several hours to a day) characteristic symptoms are observed, which, especially in the case of an appropriate epidemiological situation, make it possible to suspect cholera: anxiety, weakness, rumbling in the abdomen, pain in the chewing and calf muscles, sweating, dizziness, cold extremities.

In typical cases, cholera begins acutely with diarrhea with imperative, unexpected for the patient urge to defecate without abdominal pain and tenesmus. The stool quickly becomes watery and then resembles rice water, loses its specific smell and acquires the smell of raw fish or grated potatoes (GA Ivashentsov).
Perhaps rumbling near the navel or in the lower abdomen. After a few hours, sometimes after a day, repeated vomiting joins the diarrhea, sometimes with a fountain, without nausea, pain in the epigastric region. Vomit quickly loses its characteristic appearance, becomes watery and also resembles rice water.

Profuse diarrhea, repeated vomiting with a large amount of vomit quickly lead to dehydration. Growing intoxication, weakness, thirst, dry mouth. The skin acquires a bluish tint, becomes wet, cold to the touch, loses elasticity, its turgor decreases. The tongue is dry, the abdomen is drawn in, painless, flatulence (hypokalemia) is possible. The voice becomes hoarse, breathing quickens (tachypnea), blood pressure decreases, tachycardia is observed. Diuresis decreases, convulsions of individual muscle groups occur. Consciousness is preserved, the patients are indifferent, they experience fear. There are no significant changes in the peripheral blood at the initial stage; in the future, these changes are mainly associated with its thickening. Body temperature remains, as a rule, normal. The course of cholera can be different - from mild, erased forms to severe, fulminant, when the patient dies in a few hours. According to the severity of clinical manifestations, mild, moderate, severe and especially severe forms are distinguished. The severity of the course is determined by the degree of dehydration, hemodynamic and metabolic disorders.

The degree of dehydration underlies the clinical and pathogenetic classification of cholera. There are four degrees of dehydration, the criterion of which is a lack of body weight (%), as well as indicators of clinical and biochemical examination.

In patients with dehydration I degree diarrhea and vomiting are observed 2-4 times a day, the body weight deficit does not exceed 3%. The state of health is usually satisfactory, the patient experiences weakness, dry mouth, thirst. Physical and chemical parameters of blood remain normal. Within 1-2 days, often spontaneously, recovery occurs. Cholera with dehydration of the 1st degree manifests itself in 40-60% of patients and is recorded more often during the height and recession of an epidemic outbreak.

When dehydration II degree, which is observed in 20-35% of patients, fluid loss is more than 3% (up to 6%) of body weight. The disease has an acute onset, characterized by profuse diarrhea (stools up to 15-20 times a day), feces gradually lose their characteristic appearance, resemble rice water. Vomiting often joins, dehydration quickly increases. Patients complain of weakness, dizziness, dry mouth, thirst. The skin is dry, pale, often with unstable cyanosis, hoarseness of the voice, sometimes spasms of the calf muscles, hands, feet, twitching of the masticatory muscles, hiccups. There are tachycardia, a decrease in blood pressure to 13.3/8.0-12.0/6.7 (100/60-90/50 mm Hg).

Violation of the electrolyte balance of the blood is not permanent, hypochloremia and hypokalemia are more common. Compensated metabolic acidosis develops, in some patients the density of blood plasma slightly increases and the hematocrit number increases. Often there is an increase in the number of red blood cells and hemoglobin, which is due to progressive dehydration and blood clotting. The illness lasts 3-4 days. As in the case of degree I dehydration, spontaneous recovery without treatment is also possible; for rehydration, it is enough to drink saline solutions (for example, Oralit).

Dehydration III degree(15-25% of cases) is characterized by a loss of more than 6% (up to 9%) of body weight. Symptoms of dehydration are clear, poorly compensated without parenteral rehydration. The stool is very frequent, the feces are watery, reminiscent of rice water. There is repeated vomiting, dry mouth, significant thirst against the background of incessant urge to vomit, convulsions of all muscle groups, agitation, anxiety. A characteristic tegrade of symptoms: diarrhea, vomiting, dehydration, convulsions. These symptoms are supplemented by acrocyanosis or general cyanosis, a decrease in skin turgor (taken in a fold, it does not straighten well), on the hands the skin is in folds (a symptom of the laundress's hand). The facial features of the patient are sharpened, the look is suffering, clouded (fades cholerica), the voice is deaf, hoarse (vox cholerica), sometimes aphonia appears. Increases hypovolemia, hypoxia, thickening of the blood leads to hemodynamic disorders. Arterial pressure drops to 10.7 / 8.0-9.3 / 6.7 kPa (80/60-70/50 mm Hg), the pulse is weak, tachycardia is up to 110-130 beats per 1 min. The body temperature drops to 35.5 ° C, the mucous membranes are dry, there is grumbling in the abdomen, slight pain in the epigastric region is possible. Tachypnea, oligo-, anuria. In 50% of patients, neutrophilic leukocytosis is observed up to 9-10 9 in 1 l, ESR is increased or normal. Deepening hypokalemia, hypochloremia with hypernatremia. The mass of circulating blood plasma decreases to 33 ml/kg (normally 42-45 ml/kg), extrarenal azotemia increases.

IV degree dehydration, or cholera algid (lat. algidus - cold), is dehydration with a loss of about 10% of body weight or more. It is observed during outbreaks of cholera in 8-15% of patients. Before the development of the algid state, short-term manifestations of the previous stages of dehydration are possible, they quickly (in a few hours) replace each other. The patient's condition deteriorates sharply. The progression of the disease leads to the development of hypovolemic shock. Due to intestinal paresis, diarrhea and vomiting may temporarily decrease or even stop, but sometimes they resume against the background of rehydration or after it has ended. All symptoms of dehydration are pronounced. Body temperature drops to 35 ° C or to “cadaveric temperature” (31 ° C) (M.K. Rozenberg). The skin is cold (“like ice”), covered with sticky sweat, its turgor and elasticity are sharply reduced (the fold does not level out, a symptom of the laundress’s hand), the sensitivity of the skin decreases (yellow plaster passes without a trace). Facial features become even more aggravated, a typical "cholera face", cyanosis around the eyes is noticeable - a symptom of dark (cholera) glasses, and with further dehydration - a symptom of the setting sun. The eyes of the patient are hot, the eyeballs are shriveled, blindness. Parts of the body that protrude - ears, nose, fingertips, lips - are gray-cyanotic or purple. Voice Noiseless or aphonia.

Severe shortness of breath (50-60 respiratory excursions in 1 min), often patients breathe through their mouths. All the muscles of the chest participate in the act of breathing.
Convulsions of a tonic nature extend to all the pectoral muscles, including the diaphragm, which leads to a strong hiccups. Anuria. The pulse is threadlike (up to 140 per minute or more), the heart sounds are sharply muffled, the II tone may disappear, the II tone is replaced by noise, the pericardial friction noise turns out to be. The patient is in a state of deep prostration. The blood is sharply thickened, the number of erythrocytes is 6-8-10 12 per 1 liter, hemoglobin is about 180 g / l or more, leukocytes are 80-10 9 per 1 liter, the hematocrit number reaches 0.6 or more, ESR is normal. Hypokalemia is observed - below 2.5 mmol / l. If timely treatment is not carried out, the disease passes into the phase of asphyxia, cholera coma. Death occurs against the background of loss of consciousness, repeated attacks of collapse, tachypnea, convulsions. In lethal cases, the duration of the disease does not exceed 3-4 days.

The reactive period (recovery) in cholera can occur against the background of dehydration of any degree, including algid. Its beginning is difficult to predict. This period is characterized by a gradual fading of the acute manifestations of the disease, the patient's skin acquires a normal color, warms up, its elasticity is restored, the pulse gradually approaches normal, heart sounds become louder, blood pressure rises, voice becomes stronger, urine appears to polyuria.

Gradually within 2-3 days the body temperature returns to normal. Such sharp reverse changes in most cases quickly disappear with intensive rehydration therapy. Atypical forms of the disease include fulminant (fulminant) cholera, in which there is a sudden onset and rapid development of dehydration, as a result of which hypovolemic shock, convulsions of all muscle groups develop rapidly, symptoms of encephalitis appear cholera coma sets in. Some researchers (A. G. Nicotel) explain this form of the disease by the possibility of staying and multiplying Vibrio cholerae in the biliary tract, where the pathogen enters through the common bile duct from the duodenum, where it had previously multiplied to a huge amount. A critical condition develops at lightning speed due to the ingestion of a large amount of toxic products of cholera vibrios into the blood through the intact wall of the gallbladder in the early period of the disease.

Dry cholera (cholera sicca) is a very severe (“tragic”) form of the disease with a malignant course. In patients with this form, among full health, a sharp weakness appears, collapse, shortness of breath, convulsions, cyanosis, and a coma quickly develop. This form for several hours leads to death in case of circulatory and respiratory failure. This variant is rarely observed, as a rule, in malnourished patients.

The erased form of the disease is characterized by indistinct symptoms and a mild course (more often observed in the case of El Top cholera).

The course of cholera in preschool children has some peculiarities. Gastroenteritis, as a rule, develops less frequently and the disease proceeds in the form of enteritis. More often, severe forms are observed, since children are more difficult to tolerate dehydration. They often have lesions of the central nervous system, the manifestations of which are adynamia, convulsions, clonic convulsions, profound impairment of consciousness, coma. In children, dehydration develops faster, the degree of which is more difficult to determine due to the relatively large volume of extracellular fluid, so relative plasma density indicators are less informative. Children have a greater tendency to hypokalemia, a significant increase in body temperature. The diarrhea is debilitating. Possible meningeal symptoms.
Similar manifestations can also be observed in the elderly due to unresponsiveness (avitaminosis, intercurrent diseases). Mortality reaches 20-40% or more.

Features of the modern course of cholera are associated with the specifics of the vibrio El Gor. Cholera caused by this pathogen has a predominantly milder course, erased and atypical forms are more often observed with a long post-infectious, often healthy vibrio carrier.

Complications of cholera

One of the complications of cholera is cholera typhoid (Griesinger), which often develops at the beginning of the reactive period due to the penetration of putrefactive or other microorganisms from the intestine into the blood against the background of deep suppression of the body's immunological reactivity. In the event of such a complication, a sudden increase in body temperature to 39 ° C and above is observed. Headache, drowsiness, typhoid condition, hepatolienal syndrome appear. A roseolous rash is possible on the skin, causative agents of intestinal infections (Salmonella, Escherichia, etc.) are isolated from the blood. Recovery is possible, but comes very slowly.

Other complications of cholera are pneumonia, which is often accompanied by pulmonary edema, as well as phlegmon, abscess, purulent parotitis, cystitis, etc.

cholera prognosis

Due to the widespread use of pathogenetic treatment (rehydration), lethality from cholera has sharply decreased, but with dehydration of III-IV degree, the prognosis is always serious. Recently, mortality has decreased from 6 to 1%.

cholera diagnosis

During an epidemic outbreak of cholera and the presence of typical manifestations of the disease, diagnosis is not difficult and can only be based on clinical symptoms. However, in a mild form of the disease with dehydration of I and II degrees, significant diagnostic difficulties arise, especially in the inter-epidemic period.

The main symptoms of the clinical diagnosis of cholera are:

• classic tetrad - diarrhea, vomiting, dehydration (isotonic dehydration), convulsions,
• acute onset of the disease with diarrhea and subsequent vomiting (without nausea, abdominal pain, tenesmus), vomit and feces in the form of rice water or whey,
• subnormal body temperature;
• acrocyanosis (total cyanosis), symptoms of cholera face, laundress hand, cholera fold, cholera glasses;
• hoarse noiseless voice (up to aphonia), tachypnea, tachycardia, lowering blood pressure (up to collapse), oligoanuria.

Of great importance for establishing the diagnosis are the data of the epidemiological history, the presence of a similar disease in the environment of the patient.

Specific diagnosis of cholera

Both classical and express methods are used. The bacteriological method, which is the main and decisive in the laboratory diagnosis of cholera, belongs to the classical studies. For bacteriological examination, feces and vomit are used. If it is not possible to deliver the material to the laboratory within 3 hours, preservative media are used (alkaline 1% peptone water, Reed's bismuth sulfite medium, etc.).

The material is collected in individual vessels, washed from disinfectant solutions. For research, 10-20 ml of material is taken, which, using disinfected boiling spoons, is collected in sterile jars or test tubes. To obtain the material, rectal cotton swabs are also used, less often rubber catheters. The material is delivered to the laboratory in a metal container by special vehicles. When receiving and transporting the material, strictly observe the rules of personal safety. The material is sown in 1% lepton water (previous result after 6 hours) followed by inoculation on thick nutrient media. The final result is obtained in 24-36 hours.

A significant drawback of the classical methods of laboratory diagnostics is the relatively long duration of the entire period of identification of the pathogen. Therefore, express diagnostic methods are increasingly being used in cholera: immobilization reactions, microagglutination of vibrios with anti-cholera O-serum using phase-contrast microscopy (the result is obtained after a few minutes), macro-agglutination using specific anti-cholera O-syrovatkin and immunofluorescence reaction (result after 2 - 4 hours).
For the purposes of serological diagnostics, RIGA, RN, and ELISA are used.
The method of identifying the cholera phage is also used, but it has an auxiliary character.

Differential diagnosis of cholera

Cholera should be differentiated from escherichiosis, food poisoning, staphylococcal food poisoning, shigellosis, rotavirus gastroenteritis, green fly agaric poisoning, pesticides, salts of heavy metals.

With salmonella gastroenteritis dehydration rarely reaches grade III or IV. First, there is pain in the abdomen, nausea, vomiting, body temperature rises, and only later diarrhea joins, while cholera begins with diarrhea, and vomiting occurs later, against the background of progressive dehydration. In patients with salmonellosis, green feces mixed with mucus, smelly. Enlargement of the liver and spleen is often detected, which is not typical for cholera.

shigellosis characterized by spastic pain in the left iliac region, tenesmus, a small amount of feces mixed with mucus and blood, which is not present in cholera, there are almost no signs of dehydration.

In patients with Escherichiosis, body temperature rises, dehydration (exicosis) gradually develops, and the fecal nature of feces persists for a long time, which in young children are orange.

Rotavirus gastroenteritis observed in the form of outbreaks, mainly in the autumn-winter period, feces are foamy, dehydration does not reach the same degree as in cholera. Often revealed hyperemia and granularity of the mucous membrane of the oral part of the pharynx.

Fly agaric poisoning(pale toadstool) often, like cholera, is accompanied by an enteritis syndrome, but it is characterized by sharp pains in the abdomen and severe liver damage with jaundice. It is also necessary to differentiate cholera from poisoning with arsenic compounds, methyl alcohol, antifreeze (history is of great importance), as well as from severe forms of malaria.

cholera treatment

Primary and most effective in patients with cholera is pathogenetic therapy. It covers therapeutic measures aimed primarily at combating dehydration and loss of mineral salts by the patient's body, with acidosis, as well as neutralizing and removing toxins from the body, destroying the pathogen.

Since the severity of the course of cholera is due to acute dehydration, timely and high-quality rehydration by parenteral administration of isotonic saline solutions should be considered the most significant. Rehydration is carried out in two stages: the first is primary rehydration in order to compensate for the water and electrolyte deficiency that already exists, the second is to correct the loss of water and electrolytes, which is ongoing.

A prerequisite for the effectiveness of rehydration therapy is the solution of three questions: what solutions, in what volume and how they should be administered to the patient.

The first stage of rehydration should be carried out during the first hours of illness. The volume of solutions should be equal to the initial deficit in body weight, which can be found out from a survey of the patient or his relatives. There are several ways to determine the total volume of fluid needed for rehydration. The simplest is the already mentioned method for determining the volume of fluid by weight loss.
To determine the required volume of fluid, you can use the relative density of the patient's blood plasma. So, for every thousandth of an increase in the relative density of plasma over 1.025, 6-8 ml of liquid per 1 kg of the patient's weight is administered parenterally.

At the initial stage of rehydration therapy, it is mandatory to determine the required volume of rehydration fluid every 2 hours. To do this, the relative density of the blood plasma, the blood ionogram, and the ECG are recorded with the same frequency. It is also advisable to periodically determine the hemagocrit number of the total level of blood plasma protein and the number of erythrocytes.

Salt solutions are used for parenteral rehydration. "Kvartasil" contains sodium chloride - 4.75 g, potassium chloride - 1.5, sodium acetate - 2.6, sodium bicarbonate-1 g per 1 liter of water for injection, Phillips solution No. 1 ("Trisil") - sodium chloride -5 g, sodium bicarbonate - 4, potassium chloride - 1 g per 1 liter of water for injection, Phillips solution No. 2 with normal levels of potassium in the blood plasma - sodium chloride - 6 g, sodium bicarbonate - 4 g per 1 liter of water. In addition to the above solutions, you can use "Acesil", "Chlosil", "Lactosil".

Of great importance is the rate of introduction of solutions. So, in case of III-IV degree dehydration in the first 20-30 minutes of primary rehydration, 2-3 liters of solution are injected in a jet at a rate of 100 ml / min, during the next C-40 minutes - 50 ml / min (1.5-2 l), in the last 40-50 minutes - 25 ml / min (1.5 l). Concerns about the dangers of rapid administration of isotonic saline solutions are exaggerated. Experience shows that it is rapid rehydration that contributes to the normalization of hemodynamics. Subcutaneous administration of solutions to patients with cholera is impractical and is no longer used. A necessary condition for rehydration therapy is to control the temperature of the applied solutions (38-40 ° C).

Patients with dehydration I, and sometimes II degree, it is possible to rehydrate orally. For this purpose, "Oralit" ("Glucosolan") of the following composition is used: sodium chloride - 3.5 g, sodium bicarbonate - 2.5, potassium chloride-1.5, glucose - 20 g per 1 liter of boiled drinking water. You can also use "Regidron", "Gastrolit" and others. It is recommended to dissolve weighed portions of salts and glucose in water with a temperature of 40-42 ° C immediately before use. In case of repeated vomiting, oral rehydration should be avoided and parenteral (intravenous) solutions should be administered.

Jet infusion of solutions can be stopped only after the normalization of the pulse, blood pressure, body temperature. The criterion is also the elimination of hypovolemia, blood clotting, acidosis.
At the end of primary rehydration, compensatory rehydration is continued (second stage). Correction of fluid loss and metabolic disorders is carried out taking into account the studied dynamics (every 4-6 hours) homeostasis indicators, the amount of feces and vomit. In severe cases, the correction continues for several days. For the purpose of compensatory rehydration, the above isotonic solutions are used, which are most often administered intravenously (drip).

Rehydration therapy can be stopped only in conditions of a significant decrease in the volume of feces, the absence of vomiting and the predominance of the amount of urine over the amount of feces during the last 6-12 hours. The total amount of saline solutions used for rehydration can reach 100-500 ml/kg or more.
In children, rehydration is also carried out with saline solutions, but, as a rule, with the addition of 20 g of glucose per 1 liter of solution. Children under 2 years of age are allowed to administer intravenously drip (not jet!) Up to 40% of the amount of solution determined by calculating the amount within an hour, and all primary rehydration should be carried out more slowly (within 5-8 hours).

The use of cardiac glycosides in the treatment of patients with decompensated dehydration is contraindicated, since pressor amines deepen microcirculation disorders and contribute to the development of kidney failure.

In the complex therapy of patients with cholera, antibiotics are used. In this case, the principles of antibiotic therapy should be observed:

1. prescribing an antibiotic after receiving material for bacteriological examination,
2. continuity of drug intake (including night hours),
3. parenteral administration, and after the cessation of vomiting - oral,
4. determining the sensitivity of the pathogen to antibiotics.

Patients are prescribed inside tetracycline - 0.3 g 4 times a day or doxacycline - 0.1 g every 12 hours. Levomycetin is also used - 0.5 g 4 times a day.
The use of antibiotics reduces the duration of diarrhea. The course of antibiotic treatment, regardless of the degree of dehydration, should be at least 5 days.

According to the same scheme, the treatment of bacterial carriers is carried out. If necessary, patients with cholera are given antibiotics prescribed parenterally.
Patients with cholera do not need a special diet. First, diet number 4 is prescribed, and after 3-4 days - a general one with a predominance of foods that contain a lot of potassium (for example, potatoes).

cholera prevention

Patients are discharged from the hospital after receiving negative results of a bacteriological study, which is considered before discharge, 24-36 hours after the end of antibiotic treatment. Examine feces three times, and in persons from among the decreed contingents, also bile (portions B and C) - once.
The most important element of prevention is the early detection of patients and vibrio-infection and their isolation.

Hospitalization is carried out in hospitals of three types, taking into account the epidemiological feasibility:

1. cholera isolator, in which cholera patients are hospitalized;
2. provisional isolation ward (hospital), where all patients with gastrointestinal diseases are hospitalized from the focus to establish an accurate diagnosis,
3. observational isolator (hospital) for examination of persons who were in contact with the patient or bacteria carriers. Quarantine measures (isolation of contact persons) are carried out within 5 days. If cholera patients are found among this contingent, the quarantine period is determined again from the last contact with the identified patient.

Persons who have been in close contact with a cholera patient are given emergency prophylaxis. For this purpose, tetracycline is used - 0.3 g 3 times a day for 4 days. The dose for children is reduced according to age.

A thorough epidemiological study of each case of cholera (vibrio carrier) is carried out. When cases of cholera are detected, an operational epidemiological analysis is carried out and the boundaries of the cell are clarified. The necessary means are preventive and final disinfection, bacteriological examination of the causative agent of cholera of environmental objects.

If NAG-vibrios are detected during the examination, such patients are immediately hospitalized, and the necessary materials are examined in the outbreak for the cholera causative agent.

In the presence of cases of cholera, the use of water bodies and the migration of the population are limited. Extensive sanitary and educational work is being carried out.
Prevention of cholera provides for the sanitary protection of borders from the importation of infection from outside. In the event of an unfavorable epidemiological situation, the issue of vaccination is decided. It is administered to children over 7 years of age and adults with corpuscular cholera vaccine and cholerogen anatoxin once at a dose of 0.8 ml. Immunity after vaccination persists for 4-6 months. Revaccination is carried out according to epidemiological indications not earlier than 3 months after the primary vaccination.

She invaded Paris at the end of March 1832. Failing to meet a worthy medical rebuff, she destroyed half of the infected. It manifested itself with a set of terrible symptoms unlike anything else. No tragic tuberculosis cough, no romantic malarial fever. The faces of the patients in a matter of hours wrinkled from dehydration, the tear ducts dried up. The blood became viscous and congealed in the vessels. Oxygen-deprived muscles cramped up to breaks. As organs failed one after another, the victims fell into a state of shock, while being fully conscious, spewing liquid stools in liters. Terrible stories circulated around the city about how a man, having sat down to dine, was already dead for dessert; about how the passengers of the train suddenly fell dead in front of the entire compartment. And they didn’t just grab their hearts while falling to the floor, but uncontrollably emptied their intestines. It was a humiliating, savage disease, it offended the noble feelings of the Europeans of the 19th century.

The disease brought the city's physicians into disarray. One of them reported on the examination of a couple who had contracted cholera. The bed and linen "were soaked with a clear, odorless liquid," and if the woman constantly asked for water, then the man next to her lay unconscious. The doctor tried to feel for a pulse. “I have never touched such skin, although I have been to the deathbed many times. The touch made my heart go cold. “I couldn’t believe that there was still life in the body I touched.” The skin on the hands of the doomed couple was wrinkled, as "after a long fuss in the water" "or rather, like a corpse that has lain for more than one day"

This is what cholera looks like - one of the most, if not the most dangerous disease of the 19th century, it struck everyone indiscriminately, kings, dukes, peasants, emigrant sailors - no one resisted this terrible infection, which was represented by cholera vibrio. It is this bacterium that is responsible for seven full-blown pandemics that claimed millions of lives in the 19th and 20th centuries.

"In the fifties of the 19th century, the death rate from the cholera epidemic in Russia alone amounted to more than a million people, it was the deadliest epidemic in the whole century."

Where did this cholera vibrio come from and how did it manage to get used to the human body? a detailed look at tiny crustaceans called copepods will give us the answer. They are about a millimeter long, teardrop-shaped, with a single bright red eye. They are classified as zooplankton - they cannot move independently in the water for long distances and travel with the flow along with the water masses. Long mustaches, like wings, help them navigate the streams of water, and although few know about their existence, this is the most numerous multicellular animal in the world.

More than two thousand copepods can live on one sea cucumber. During the season, each individual can produce up to 4.5 billion offspring.

Yes, if you look at our scale, then this is only four and a half billion millimeters, not so much, but this is after all the offspring of only one individual, and if there are four and a half billion of them? Agree, completely different numbers :)

Vibrio cholerae is the bacterial partner of copepods. Like other members of the Vibrio genus, it is a bacterium that looks like a microscopic comma. Although the vibrio can survive on its own in water, it prefers to stick around the copepods inside and out, attaching to their egg chambers and lining the inside of the intestine. There the vibrio performs a very important ecological function. Like all crustaceans, copepods are covered with chitin, a kind of protective shell, and due to the fact that they grow all their lives, as they grow, they shed a tight shell into the water. Every year, copepods leave a total of 100 billion tons of chitin on the seabed, which are then absorbed by vibrios, processing together 90% of chitinous debris. If not for them, mountains of exoskeletons grown and then dropped by copepods would soon use up all the carbon and nitrogen in the ocean. This dangerous vibrio performs such an important ecological function, which has ruined millions of lives and continues its bloody business to this day.

So dangerous and so necessary, but is he really dangerous? Not really, this vibrio itself is not dangerous, its mutant brother is dangerous, who managed to adapt to the human body and firmly settle in it.

Vibrios and copepods bred and multiplied in warm brackish river deltas, where fresh and sea water mixes. Such, for example, as the Sundarbans - vast marshy forests in the basin of the world's largest marine Bay of Bengal. They did not grieve for themselves until a man came to their homeland, and not a simple man, but enterprising English colonialists. With the hands of thousands of hired workers from the local population, they cut down mangroves, built dams and planted rice. Chroniclers of the 19th century described these places as

"flooded lands that are covered with jungle, choking with malaria, teeming with wild animals", but "incredibly fertile"

By the end of the 19th century, human settlements occupied about 90% of the once pristine, impenetrable - and infested with copepods - Sundarbans. Local fishermen and peasants constantly lived knee-deep in brackish water, just in places ideal for reproduction of copepods. A fisherman rinses his face, a farmer takes water from a heated well full of copepods, and so on. Due to such close contact with copepods, and at the same time with vibrio cholerae, because one such copepod can contain up to 7000 vibrios, these vibrios have an excellent opportunity to switch to the human body.

As a zoonosis, Vibrio cholerae only infected people who came into contact with its "natural reservoir", i.e. copepods. In order to be transmitted from person to person, it needed favorable conditions: a warm comfortable environment, constant contact with a person, and a little bit of evolutionary time.

The vibrio had plenty of ways to tune in exclusively to humans, but he secured his future by learning to create microcolonies in the intestines and produce a toxin. The latter skill became his main advantage. By producing a toxin, the vibrio forced the rest of the intestinal bacteria to be flushed out with a rapid stream of liquid, thus getting rid of competitors, allowing the vibrio, whose microcolonies tightly clung to the intestinal walls, settle there without any problems.

Also, due to uncontrolled violent defecation, the cholera vibrio penetrated anywhere, on unwashed hands through which it fell into the next victim or, together with the contents of the latrines, entered the sewage, polluting them, etc. By the way, the inept handling of waste products by the Europeans of that time played into the hands of Cholera. In a compartment, of course, with medical ideas about the origin of all diseases. These two pillars of world culture in the 19th century, or rather, unsanitary conditions and a misconception about bacteria, or rather its absence, played a decisive role in the spread of infection to the whole world.

Firstly, in those days it was customary to dump all the waste into the rivers, it was believed that if there was no smell, then there was no problem. According to the Hippocratic miasmatic theory of the origin of all diseases, it was generally accepted that all infection is in the air. It was not customary to talk about bacteria in those days, and this is taking into account the fact that the microscope was invented already two centuries before (but they say that they were not quite suitable for examining bacteria specifically in them, but he did not specify). The medical community was unshakable and did not fully recognize the nature of the occurrence of cholera, namely that the vibrio is transmitted with water (even when it was cracked on every corner), and that if the water was carefully purified or taken from the river above (before how tons of excrement of infected townspeople pour into it), then people, nevertheless, will not depart so rapidly into another world.

They also refused to treat cholera with saline, which made up for the loss of fluid in the body and gave simply enormous chances of surviving the sick. The logic of the treatment was to compensate for the loss of fluid caused by vomiting and diarrhea, because the body simply dried out from the loss of fluid. This method was denied all the same because it contradicted the Hippocratic paradigm. According to the Hippocratic doctrine, epidemic diseases like cholera spread through fetid fumes, through the so-called miasma, poisoning those who inhale them. Therefore, cholera patients are tormented by indomitable vomiting and diarrhea: the body struggles to expel the poison that has entered it with miasma. At that time, it was more than logical, if only because no one had any other explanation, and if someone did, it was immediately suppressed by the indomitable power of the authority of pundits.

To counteract these processes with the help of salt water and anything else, in principle, looked from a philosophical point of view as erroneous as picking out a crust on a wound today. Even a good example of the operation of this method from William Stevens, a simple doctor working in the Virgin Islands, did not help. He didn't help because he was Stevens, he was nobody, and in those days, if nobody claims to stagger the paradigm, he goes to hell. Stevens did an amazing experiment, in 1832 he fed more than 200 cholera patients in one London prison with salty liquid - the death rate from the disease was only 4%. This was dozens of times superior to the best results that the luminaries of that time could only demonstrate. But they did not believe him and did not take him seriously. Experts who visited the prison where Stevens conducted his successful experiments did not accept his successes and stated that

"I did not observe a single case whose symptoms would correspond to cholera ones."

They were ready to recognize as cholera patients those who fought in agony and were near death, and since those were not found, then in fact there was no cholera in prison. Logics:)

In scientific circles, Stevens was called a charlatan and advised to forget about his useless “scam”. Reviewers completely ridiculed him -

“Unlike pork and herring,” scoffed one of the reviewers in 1844, “salting the sick does not do much to prolong their lives.”

There were more and more such precedents, and the Hippocratic miasmatic theory fell like a sandcastle. The authoritative scientist of that time - John Snow - managed to collect irrefutable evidence in his favor and prove that cholera is infected precisely through the use of contaminated water. It has been a long time since Snow's ideas began to be heeded. But still, the reconstruction of the sewerage, which did not involve dumping waste into the river, but storing it in separate places, treating patients with saline solutions and other methods, allowed the world to get rid of such a scourge as cholera or to reduce its victims to a minimum.

But still, this does not mean that cholera has completely retired, in the modern world this disease is more typical for developing countries, where it is still very bad with clean drinking water and a normal sewerage system. For example, in 2010 there was a cholera outbreak in Haiti, more than two hundred thousand people were infected and four and a half thousand died. So, it's too early to sing praises and bury this serious misfortune. Although there are vaccines against this disease, most of which are effective only for half a year, and then the effectiveness of the action gradually decreases. But the good news is that such a creepy and rapidly developing disease is still treated and treated quite successfully, even though it is still an unpleasant thing.

Cholera - [History of Medicine]