A researcher ingests Vibrio cholerae. History of the study of cholera. Sources and causes of cholera Pathogenesis and pathomorphology of cholera

Doctors say that infectious diseases have claimed more lives throughout human existence than continuous wars. The leading role in this belongs especially to dangerous infections, which includes cholera. Thousands of people die from this disease every year, the exact number of deaths is difficult to calculate, and statistics are deliberately downplayed.

Why is cholera so difficult to fight? What features does this bacterium have? How does the infection occur and why does the disease claim millions of lives? How is cholera transmitted and what can be done to prevent it? What would be helpful for people traveling to countries with annual disease outbreaks to know?

What is cholera

Throughout the history of mankind, scientists have counted 7 massive outbreaks or pandemics of cholera, each of which claimed thousands and even millions of lives. Now hundreds and thousands of people die every year, depending on the area where the infection occurs.

But cholera was known in ancient times. Hippocrates and Galen also spoke about it in their works. In European countries, they became more interested in the causative agent of the disease in the 19th century, which contributed to a more thorough study of not only the causes and routes of transmission of cholera, but also measures to prevent the disease. Scientists believe that this was the impetus for improving the water supply system. The interest of biologists helped to discover two main variants of the pathogen - classical and El-Tor vibrio, named after the station where this species was discovered.

Due to frequent outbreaks of the disease and a large number of deaths, cholera is a particularly dangerous type of infection. Therefore, the incidence rate is monitored annually by local health systems and WHO.

The causative agent of cholera

The infection is of the bacterial type, that is, the causative agent of cholera is bacteria. About 150 serogroups of vibrios are known in nature. But the cause of this serious illness is two variants of the pathogen - classic and El Tor.

Vibrio cholerae (vibrio cholerae) is a special type of bacteria in the form of straight or slightly curved rods with one or two flagella. They do not form spores or capsules, love an alkaline environment (therefore they prefer to reproduce in the human intestine), and are easy to grow in a laboratory. Another feature of bacteria is their high enzymatic activity, which helps them decompose many complex carbohydrates in the human body and beyond.

The distinctive features of the causative agent of cholera are as follows.

1. Sensitive to dryness and light.
2. Vibrio cholerae does not feel comfortable in acid and quickly dies under the influence of antiseptics and conventional disinfectants.
3. It does not like high temperatures (it dies almost immediately when boiled) and the effects of antibiotics.
4. It persists for a long time in feces, bed linen, and soil.
5. The causative agent of cholera loves water, that is, it is able to survive there for a long time.
6. There are two important differences in the structure of bacteria - endo and exotoxins. These are protein-lipid structures that are the first to be released in the event of destruction of the pathogen.
7. Cholera toxin or exotoxin is its damaging factor, which leads to numerous changes in the human body, in particular, it is released in the intestines, which is why it is also called enterotoxin.
8. Another feature of Vibrio cholerae is that it can exist peacefully in the human body for a long time thanks to antigens (flagellar or H and heat-stable or endotoxin O).

Bacteria are in environment and in the human body for years and even centuries.

Epidemiology of cholera

Cholera epidemics occur annually and involve millions of cases and thousands of deaths. The number of countries where it is not possible to get rid of the pathogen includes mainly developing ones. Southeast Asia is the leader in the number of cases. The countries of Africa and Latin America are not far behind them.

Sporadic cases of cholera (periodic outbreaks of the disease) are also observed in Russia. In most cases, these are imported infections or the result of the influence of neighboring countries.

From the beginning of the 19th century, namely in 1816, until the end of the 20th century in 1975, scientists counted 7 cholera pandemics, when the disease easily spread to many countries (Russia, India, England, USA, Japan). And although no more pandemics have been recorded yet, cholera is still among the most dangerous diseases, since it is not possible to destroy the pathogen.

Why can't you get rid of bacteria?

1. Without special treatment, vibrios are stable in the external environment.
2. The main risk factors for cholera infection are contaminated water, contact with a sick person or bacteria-transmitting agent, and consumption of contaminated foods. The disease still flourishes due to imperfect water supply systems in developing countries, lack of disinfection of sewage water and a large number of cholera bacteria. According to doctors, the number of the latter exceeds the number of sick people by 4 times.
3. Bacteria are able to mutate, which helps them become more resistant in the external environment. In the history of the development of infection, a case was recorded when cholera vibrio was re-isolated from sludge treated with disinfectants, but no cases of the disease were observed in humans.

Reasons for the spread of the disease

How can you get an infection? The transmission mechanism characteristic of cholera is fecal-oral, that is, through contaminated environmental objects. It is not always possible to perfectly treat all surfaces and household items around a sick person. At the same time, the pathogen, being around, is transmitted to healthy people through unwashed hands.

What are the routes of transmission of cholera?

1. Waterborne when swimming in open contaminated waters, if you drink water contaminated with cholera bacteria or wash food in such water. This path is considered the leading one.
2. Contact during communication or as a result of touching an infected person or bacteria carrier at the time the cholera pathogen is released into the environment.
3. Can a person become infected with cholera through food? - yes, it is called alimentary, when a person eats contaminated foods. Moreover, they themselves may contain cholera vibrios or the bacteria may get onto the products during processing when an infected person, say, sneezed on the product during active bacterial excretion.

What are the ways for bacteria to enter the human body during cholera? - only through the mouth. It has been established that many animals are capable of accumulating the causative agent of cholera and spreading it when they eat them. For example, unprocessed oysters, fish, shrimp and shellfish, in which the pathogen sometimes persists for years, can serve as a temporary reservoir of infection.

Another cause of cholera infection or one of the factors of infection transmission are insects, on whose body vibrios can be found after contact with a patient. Therefore, during the development of epidemics, it is better to avoid encounters with flies, cockroaches, and mosquitoes.

The reservoir of infection is always a sick person who can infect others for several weeks after the illness. People with lungs also play an important role in the spread of cholera. chronic forms diseases during exacerbation and bacteria carriers.

What happens in the human body during cholera infection?

Cholera is cyclical acute infection, which may not develop if the person is absolutely healthy and the amount of pathogen that enters the body is very small. This happens because one of the significant barriers to infection is the acidic environment of the stomach. Bacteria are not friendly with an acidic environment; they quickly lose their pathogenic properties in the gastric contents.

But, having reached the small intestine, the situation changes dramatically, because there is already an alkaline environment in which vibrios feel very comfortable. Some bacteria are destroyed along the way, releasing endotoxin. Some of them reach the intestines. By using special education- fimbriae (small filamentous processes) they are attached to the walls of the small intestine and remain here for a long time.

The pathogenesis of cholera is directly related to the action of exotoxin, which penetrates enterocytes through special active zones of small intestinal cells. This destructive factor leads to an imbalance in the functioning of enzyme systems. Therefore, a large amount of fluid and electrolytes begins to be released into the intestines, which include potassium, chlorine, sodium and others. necessary for the body elements.

As a result of this action of the exotoxin, a sharp loss of fluid occurs, because all of it rushes out.

Degrees of dehydration in cholera

Repeated vomiting and diarrhea are important prognostic signs of cholera, thanks to which the severity of the infection and more can be determined. Based on the amount of fluid lost by the body per day, one can make a prediction regarding the consequences of the disease.

How many degrees of dehydration (dehydration) are there in cholera? There are 4 in total, but there are minor differences between children and adults.

1. I degree is characterized by fluid loss in adults from 1 to 3%, in children about 2%.
2. II degree - from 4 to 6%, in children up to 5%.
3. III degree - the total amount of fluid lost does not exceed 9%, for children the upper limit is 8%.
4. IV degree - critical, when a person loses moisture by 10% or more total mass body, in children this degree is set if a loss of 8% or more has occurred.

Symptoms of cholera

The manifestations of the disease are practically no different when infected with classical vibrio and El Tor vibrio. Incubation period Cholera lasts on average 48 hours, the maximum is 5 days, and with a lightning-fast course of the disease it does not exceed several hours.

Typically, a distinction is made between mild, moderate and severe degrees of infection.

The classic version of the disease is a moderate course. The symptoms of cholera are as follows.

During an examination of a sick person, the doctor notes an increase in heart rate, a decrease blood pressure, dry tongue and skin. Sometimes the skin takes on a bluish tint (cyanotic).

Under ideal conditions, diarrhea lasts from a few hours to 1-2 days, and the frequency of stool depends on the severity of the disease.

Mild cholera

This is one of the most favorable courses of the disease.

Signs of mild cholera are:

• diarrhea no more than 10 times during the day;
• dry mouth, weakness and thirst;
• vomiting may be absent or infrequent;
• first degree dehydration;
• all symptoms disappear within two days.

Cholera in this case ends with complete recovery without any complications.

Moderate infection

If in the first case patients often do not even go to the doctor, then the average degree of cholera will require medical care.

The moderate course of the disease is characterized by:

• fast start;
• frequent stools, up to 20 times a day, which gradually takes on the appearance of rice water;
• despite diarrhea, abdominal pain may not bother a person, but tenesmus or false urge to go to the toilet are observed;
• frequent vomiting, which is not preceded by nausea, as is the case with other infectious diseases;
• thirst, cramps and severe general weakness;
• second degree of dehydration of the body.

Severe cholera

One of the most dangerous courses of the disease is its severe degree. With this type of cholera, stools exceed 20 times a day. There is a sharp deterioration in the condition, a pronounced loss of fluid, in which there is dry skin, shortness of breath, cyanotic skin, a decrease in the amount of urine excreted per day (oliguria) to its complete absence (anuria). Dehydration corresponds to stage 3 of the disease.

As cholera progresses, the typical appearance of a sick person is characteristic:

• sunken eyes, increased dryness of mucous membranes and skin;
• the skin on the hands wrinkles - “washerwoman’s hands”;
• in humans long time consciousness is preserved;
• the amount of urine excreted decreases during the day, which indicates the onset of kidney problems;
• spasms of individual muscle groups appear;
• Body temperature may be within normal limits or slightly reduced.

If treatment is not started in a timely manner, the number of deaths from this form of cholera reaches 60%.

Other types of cholera

Cholera is an acute infection with diverse clinical manifestations. In addition to the classic course of the disease, there are several other forms that you need to know about.

1. The so-called dry cholera. It is characterized by an acute onset without diarrhea and vomiting. The danger of the disease is that dehydration and shock develop almost before our eyes. It is typical for weakened patients who already had any diseases before infection.
2. The fulminant form of cholera occurs over several hours or days. With this variant of the course of the disease, all of the above symptoms occur quickly, the person “burns out” right before our eyes.

These are the most unfavorable variants of the course of cholera, which in most cases end in death, even with timely treatment.

Features of the development of cholera in children

Children, like older people, belong to a special category of patients. Their immune system is not yet fully developed, so many infections proceed with some differences, and sometimes much more aggressively than in adults.

Cholera in children has the following differences.

1. The infection is especially severe in children in the first years of life.
2. Dehydration occurs faster, but its manifestations are not immediately noticeable. Clinical signs of dehydration are difficult to immediately detect even for a specialist.
3. Lack of potassium leads to various cramps, which occur more often.
4. During the height of cholera, children develop symptoms of brain dysfunction, which is manifested by lethargy and impaired consciousness.
5. Sometimes secondary infections occur against the background of the main one, so the body temperature is often elevated.

The child’s body is more difficult to tolerate a lack of fluid during the development of cholera, so even with a slight degree of dehydration, emergency assistance is required.

Diagnosis of infection

Diagnosis of cholera begins with clarifying the medical history, but in most cases it is carried out in stages.

Complications of cholera

Timely treatment started saved the lives of more than one person. But even high-quality assistance in full will not save you under certain conditions. What can interfere with recovery? - these are special forms of the disease.

The following complications of cholera are possible.

1. In weakened sick people, abscesses and phlegmon (purulent melting of tissues) are sometimes observed.
2. One of the rare ones in modern conditions, but quite possible complications is sepsis or bacterial blood poisoning.
3. Dehydration shock in cholera develops in the case of IV degree dehydration. This condition is characterized by: diffuse cyanosis of the skin, when certain areas of the human body acquire a bluish tint (tip of the nose, ears, eyelids); decrease in body temperature to 34 ºC; the patient's voice becomes silent; the eyes sink, the eyelids darken, which in medicine is called the symptom of “dark glasses”; The patient is characterized by severe shortness of breath and tachycardia.
4. Deterioration of brain function with the development of coma.

Despite the severe course, the prognosis for the development of even severe forms of cholera can be favorable if treatment is carried out in full. In the case of fulminant forms, a large number of deaths are observed.

Treatment of cholera

Therapy should be started immediately. Treatment of cholera is carried out only in a hospital setting in specially equipped isolated boxes or in temporarily adapted rooms, which often happens in the event of epidemics.

An undoubted advantage is the possibility of using special etiotropic therapy, which is aimed directly at destroying the causative agent of cholera.

intravenous rehydration

What is prescribed when the disease develops?

1. Rehydration or restoration of fluid loss is carried out, for which water-salt solutions are used - with mild and moderate severity of cholera, patients are given them to drink; in severe cases, it is administered intravenously.
2. At the next stage, the water-mineral composition of the blood is corrected and the same solutions are prescribed.
3. From the very first days, antibacterial drugs are prescribed, the course of treatment is at least 5 days.
4. While the condition is improving, doctors do not recommend sticking to certain diets. Meals and frequency of meals are slightly adjusted.

Prevention

Prevention of cholera is carried out directly in the foci of infection and in countries with outbreaks of the disease. That is, it can be divided into emergency and planned.

Nonspecific prevention of cholera

Anti-epidemic measures for cholera are carried out at the source of infection.

In addition, sanitary and educational work is carried out among the population about the disease and the first actions if an infection is detected. Nonspecific prevention of cholera includes monitoring of bacteria carriers. They are regularly invited to the clinic for medical examinations. In case of bacterial excretion, a preventive course of treatment is carried out.

Vaccinal prevention of cholera

Adults are urgently administered a single dose of cholerogen or toxoid in a dose of 0.8 ml. The injection promotes the development of immunity in 95% of cases. According to epidemic indications, revaccination can be carried out no earlier than after 3 months, which provides 100% protection against cholera.

But nowadays there is more modern views cholera vaccine - oral. There are currently 3 types of them.

1. “WC/rBs vaccine” consists of killed whole bacterial cells. Taken twice with a break of a week. It is administered at any age, is well tolerated and provides protection in 90% of cases.
2. “Modified WC/rBs vaccine”, which is used in Vietnam.
3. “Vaccine against cholera CVD 103-HgR” is a weakened live defense against infection. Enter once.

Cholera vaccinations are done in a clinic, or you can contact the State Sanitary and Epidemiological Service yourself. In our regions, such protection can be obtained, depending on the indications, free of charge or at one’s own request for a fee if a person travels to countries or areas with an outbreak of cholera. There is one disadvantage of such immunization - it protects for only a few months, no more than six months.

The cholera vaccine is well tolerated, reactions are observed in the form of weakness, malaise, and minor muscle pain. It is advisable to think about protection against cholera in advance, and get vaccinated no later than 10 days before departure.

Why is cholera a particularly dangerous type? Because in a few hours it can take the lives of hundreds of people. It is easy to become infected, because the pathogen can be found not only in a sick person, but also in the environment. What can save a life? Correct prevention and timely treatment.

Cholera (cholera) - acute anthroponotic infectious disease with a fecal-oral transmission mechanism of the pathogen, which is characterized by massive diarrhea with rapid development of dehydration. Due to the possibility of mass spread, it is classified as a quarantine disease that is dangerous to humans.

ICD codes -10 A00. Cholera.

A00.0. Cholera caused by Vibrio cholerae 01, biovar cholerae.
A00.1. Cholera caused by Vibrio cholerae 01, biovar eltor.
A00.9. Cholera unspecified.

Etiology (causes) of cholera

The causative agent of cholera Vibrio cholerae belongs to the genus Vibrio of the family Vibrionaceae.

Vibrio cholerae is represented by two biovars, similar in morphological and tinctorial properties (biovar cholera itself and biovar El Tor).

The causative agents of cholera are short, curved gram-negative rods (1.5–3 µm long and 0.2–0.6 µm wide), highly motile due to the presence of a polarly located flagellum. They do not form spores or capsules, they are located parallel, in a smear they resemble a school of fish, they are cultivated in alkaline nutrient media. Cholera vibrios El Tor, in contrast to classical biological variants, are capable of hemolyzing sheep erythrocytes.

Vibrios contain thermostable O-antigens (somatic) and thermolabile H-antigens (flagellar). The latter are group, and according to O-antigens, cholera vibrios are divided into three serological types: Ogawa (contains antigenic fraction B), Inaba (contains fraction C) and the intermediate type Gikoshima (contains both fractions - B and C). In relation to cholera phages, they are divided into five main phage types.

Pathogenicity factors:
· mobility;
· chemotaxis, with the help of which the vibrio overcomes the mucous layer and interacts with the epithelial cells of the small intestine;
· adhesion and colonization factors, with the help of which vibrio adheres to microvilli and colonizes the mucous membrane of the small intestine;
· enzymes (mucinase, protease, neuraminidase, lecithinase), which promote adhesion and colonization, as they destroy substances that make up the mucus;
· Cholerogen exotoxin is the main factor that determines the pathogenesis of the disease, namely, it recognizes the enterocyte receptor and binds to it, forms an intramembrane hydrophobic channel for the passage of subunit A, which interacts with nicotinamide adenine dinucleotide, causes the hydrolysis of adenosine triphosphate with the subsequent formation of cAMP;
· factors that increase capillary permeability;
· endotoxin is a thermostable LPS, which in development clinical manifestations illness does not play a significant role. Antibodies formed against endotoxin and having a pronounced vibriocidal effect are an important component of post-infectious and post-vaccination immunity.

Vibrios cholerae survive well at low temperatures; they remain in ice for up to 1 month, in sea water - up to 47 days, in river water - from 3–5 days to several weeks, in soil - from 8 days to 3 months, in feces - up to 3 days, on raw vegetables - 2 –4 days, on fruits – 1–2 days. Cholera vibrios die at 80 °C in 5 minutes, at 100 °C - instantly; highly sensitive to acids, drying and direct sunlight, under the influence of chloramine and other disinfectants they die in 5–15 minutes, are preserved well and for a long time and even multiply in open reservoirs and wastewater rich in organic substances.

Epidemiology of cholera

Source of infectious agent- human (sick and vibrio carrier).

Patients with erased and mild forms of the disease who remain socially active are especially dangerous.

Mechanism of transmission of infection- fecal-oral. Routes of transmission: water, nutritional, contact and household. The waterway is critical to the rapid epidemic and pandemic spread of cholera. At the same time, not only drinking water, but also using it for household needs (washing vegetables, fruits, etc.), swimming in an infected reservoir, as well as eating fish, crayfish, shrimp, oysters caught there and not subjected to heat treatment, can lead to cholera infection.

Susceptibility to cholera is universal. People with reduced acidity of gastric juice are most susceptible to the disease (chronic gastritis, pernicious anemia, helminthic infestations, alcoholism).

After an illness, antimicrobial and antitoxic immunity is developed, which lasts from 1 to 3 years.

The epidemic process is characterized by acute explosive outbreaks, group diseases and individual imported cases. Thanks to wide transport connections, cholera is systematically introduced into the territory of countries free from it. Six cholera pandemics have been described. The seventh pandemic caused by Vibrio El Tor is currently ongoing.

Classic cholera is common in India, Bangladesh, Pakistan, El Tor cholera is common in Indonesia, Thailand and other countries of Southeast Asia. Mostly imported cases are recorded in Russia. Over the past 20 years, more than 100 cases of importation have been recorded in seven regions of the country. The main reason for this is tourism (85%). There have been cases of cholera among foreign citizens.

The most severe cholera epidemic was in Dagestan in 1994, where 2,359 cases were registered. The infection was brought by pilgrims performing the Hajj to Saudi Arabia.

As with all intestinal infections, cholera in countries with temperate climates is characterized by summer-autumn seasonality.

Cholera Prevention Measures

Nonspecific prevention

Aimed at providing the population with good-quality drinking water, disinfecting wastewater, sanitary cleaning and improvement of populated areas, and informing the population. Employees of the epidemiological surveillance system carry out work to prevent the introduction of the pathogen and its spread throughout the country in accordance with the rules of sanitary protection of the territory, as well as a planned study of water in open reservoirs for the presence of Vibrio cholerae in sanitary protection zones of water intakes, public bathing areas, port waters, etc. d.

An analysis of data on the incidence of cholera, examination and bacteriological examination (as indicated) of citizens arriving from abroad are carried out.

According to international epidemiological rules, persons arriving from cholera-affected countries are subject to five-day observation with a single bacteriological examination.

A comprehensive plan of anti-epidemic measures is being carried out in the outbreak, including hospitalization of sick people and vibrio carriers, isolation of contacts and medical observation of them for 5 days with 3-fold bacteriological examination. Carry out current and final disinfection.

Emergency prevention includes the use of antibacterial drugs (Table 17-9).

Table 17-9. Schemes for the use of antibacterial drugs for emergency prevention of cholera

Note. When vibrios cholerae are isolated that are sensitive to sulfamethoxazole + trimethoprim and furazolidone, pregnant women are prescribed furazolidone, children - sulfamethoxazole + trimethoprim (Biseptol).

Specific prevention

For specific prevention, cholera vaccine and cholera toxin are used. Vaccination is carried out according to epidemic indications. A vaccine containing 8–10 vibrios per 1 ml is injected under the skin, the first time 1 ml, the second time (after 7–10 days) 1.5 ml. Children 2–5 years old are administered 0.3 and 0.5 ml, 5–10 years old - 0.5 and 0.7 ml, 10–15 years old - 0.7–1 ml, respectively. Cholerogen toxoid is administered once annually strictly under the skin below the angle of the scapula. Revaccination is carried out according to epidemic indications no earlier than 3 months after primary immunization.

Adults need 0.5 ml of the drug (for revaccination also 0.5 ml), children from 7 to 10 years old - 0.1 and 0.2 ml, respectively, 11–14 years old - 0.2 and 0.4 ml, 15– 17 years old - 0.3 and 0.5 ml. The international certificate of vaccination against cholera is valid for 6 months after vaccination or revaccination.

Pathogenesis of cholera

The entry point for infection is the digestive tract. The disease develops only when pathogens overcome the gastric barrier (this is usually observed in the period of basal secretion, when the pH of the gastric contents is close to 7), reach the small intestine, where they begin to multiply intensively and secrete exotoxin. Enterotoxin or cholerogens determines the occurrence of the main manifestations of cholera. Cholera syndrome is associated with the presence of two substances in this vibrio: a protein enterotoxin - choleragen (exotoxin) and neuraminidase. Cholerogen binds to a specific enterocyte receptor - ganglioside. Under the action of neuraminidase, a specific receptor is formed from gangliosides. The choleragen-specific receptor complex activates adenylate cyclase, which initiates the synthesis of cAMP.

Adenosine triphosphate regulates the secretion of water and electrolytes from the cell into the intestinal lumen through an ion pump. As a result, the mucous membrane of the small intestine begins to secrete a huge amount of isotonic fluid, which does not have time to be absorbed in the large intestine - isotonic diarrhea develops. With 1 liter of feces, the body loses 5 g of sodium chloride, 4 g of sodium bicarbonate, 1 g of potassium chloride. The addition of vomiting increases the volume of fluid lost.

As a result, the volume of plasma decreases, the volume of circulating blood decreases and it thickens. Fluid is redistributed from the interstitial to the intravascular space. Hemodynamic disorders and microcirculation disorders occur, resulting in dehydration shock and acute renal failure. Metabolic acidosis develops, which is accompanied by convulsions. Hypokalemia causes arrhythmia, hypotension, changes in the myocardium and intestinal atony.

Clinical picture (symptoms) of cholera

Incubation period from several hours to 5 days, more often 2–3 days.

Classification of cholera

According to the severity of clinical manifestations, they distinguish between erased, mild, moderate, severe and very severe form cholera, determined by the degree of dehydration.

IN AND. Pokrovsky identifies the following degrees of dehydration:
· I degree, when patients lose a volume of fluid equal to 1–3% of body weight (erased and mild forms);
· II degree - losses reach 4–6% (moderate form);
· III degree - 7–9% (severe);
· IV degree of dehydration with a loss of over 9% corresponds to a very severe course of cholera.

Currently, degree I of dehydration occurs in 50–60% of patients, II in 20–25%, III in 8–10%, IV in 8–10% (Table 17-10).

Table 17-10. Assessing the severity of dehydration in adults and children

Main symptoms and dynamics of their development

The disease begins acutely, without fever or prodromal phenomena.

First clinical signs are a sudden urge to defecate and the passage of mushy or watery stools from the very beginning.

Subsequently, these imperative urges are repeated. The stool loses its fecal character and often has the appearance of rice water: translucent, cloudy white in color, sometimes with floating gray flakes, odorless or with the smell of fresh water. The patient notes rumbling and discomfort in the umbilical region.

In patients with mild form of cholera defecation is repeated no more than 3–5 times a day, general health remains satisfactory, feelings of weakness, thirst, and dry mouth are minor. The duration of the disease is limited to 1–2 days.

For moderate severity(second degree dehydration) the disease progresses, diarrhea is accompanied by vomiting, increasing in frequency. The vomit has the same rice-water appearance as the stool. It is typical that vomiting is not accompanied by any tension or nausea. With the addition of vomiting, exicosis rapidly progresses. Thirst becomes painful, the tongue is dry, with a “chalky coating”, the skin, mucous membranes of the eyes and oropharynx become pale, skin turgor decreases. Stools are up to 10 times a day, copious, and the volume does not decrease, but increases. Single cramps of the calf muscles, hands, feet, masticatory muscles, unstable cyanosis of the lips and fingers, and hoarseness of the voice occur.

Moderate tachycardia, hypotension, oliguria, and hypokalemia develop.

The disease in this form lasts 4–5 days.

Severe form of cholera(III degree of dehydration) is characterized by pronounced signs of exicosis due to copious (up to 1–1.5 liters per bowel movement) stool, which becomes so from the first hours of the disease, and the same copious and repeated vomiting. Patients are bothered by painful spasms of the muscles of the limbs and abdomen, which, as the disease progresses, move from rare clonic to frequent and even give way to tonic spasms. The voice is weak, thin, often barely audible. Skin turgor decreases, folded skin does not straighten out for a long time. The skin of the hands and feet becomes wrinkled (“washerwoman’s hand”). The face takes on the appearance characteristic of cholera: sharpened features, sunken eyes, cyanosis of the lips, auricles, earlobes, and nose.

When palpating the abdomen, fluid transfusion through the intestines and the sound of liquid splashing are determined. Palpation is painless. Tachypnea appears, tachycardia increases to 110–120 per minute. The pulse is weakly filled (“thread-like”), heart sounds are muffled, blood pressure progressively drops below 90 mm Hg, first maximum, then minimum and pulse. The body temperature is normal, urination decreases and soon stops. Blood thickening is moderate. Indicators of relative plasma density, hematocrit index and blood viscosity are at the upper limit of normal or moderately increased. Pronounced hypokalemia of plasma and erythrocytes, hypochloremia, moderate compensatory hypernatremia of plasma and erythrocytes.

Very severe form of cholera(previously called algid) is characterized by the rapid, sudden development of the disease, starting with massive continuous bowel movements and profuse vomiting. After 3–12 hours, the patient develops a severe condition of algid, which is characterized by a decrease in body temperature to 34–35.5 ° C, extreme dehydration (patients lose up to 12% of body weight - IV degree dehydration), shortness of breath, anuria and hemodynamic disorders of the type hypovolemic shock. By the time patients are admitted to the hospital, they develop paresis of the muscles of the stomach and intestines, as a result of which the patients stop vomiting (replaced by convulsive hiccups) and diarrhea (gaping anus, free flow of “intestinal water” from the anus with light pressure on the anterior abdominal wall). Diarrhea and vomiting occur again during or after rehydration. The patients are in a state of prostration. Breathing is frequent, shallow, and in some cases Kussmaul breathing is observed.

The color of the skin in such patients acquires an ashen tint (total cyanosis), “dark glasses around the eyes” appear, the eyes are sunken, the sclera is dull, the gaze is unblinking, and there is no voice. The skin is cold and sticky to the touch, easily folds and does not straighten out for a long time (sometimes within an hour) (“cholera fold”).

Severe forms are more often observed at the beginning and at the height of the epidemic. At the end of the outbreak and during the interepidemic time, mild and erased forms predominate, indistinguishable from forms of diarrhea of ​​other etiologies. In children under 3 years of age, cholera is most severe: they tolerate dehydration less well. In addition, children experience secondary damage to the central nervous system: adynamia, clonic convulsions, impaired consciousness, and even the development of coma are observed. It is difficult to determine the initial degree of dehydration in children. In such cases, one cannot rely on the relative density of plasma due to the large extracellular volume of fluid. It is therefore advisable to weigh patients at the time of admission in order to most reliably determine their degree of dehydration. Clinical picture cholera in children has some features: body temperature often rises, apathy, weakness, and a tendency to epileptiform seizures are more pronounced due to the rapid development of hypokalemia.

The duration of the disease ranges from 3 to 10 days, its subsequent manifestations depend on the adequacy of replacement treatment with electrolytes.

Complications of cholera

Due to disturbances of hemostasis and microcirculation in patients of older age groups, myocardial infarction, mesenteric thrombosis, acute failure cerebral circulation. Phlebitis is possible (during venous catheterization), and pneumonia often occurs in severely ill patients.

Diagnosis of cholera

Clinical diagnosis

Clinical diagnosis in the presence of epidemiological data and a characteristic clinical picture (onset of the disease with diarrhea followed by vomiting, absence pain syndrome and fever, the nature of the vomit) is not complicated, however, mild, erased forms of the disease, especially isolated cases, are often visible. In these situations, laboratory diagnosis is critical.

Specific and nonspecific laboratory diagnostics

The main and decisive method for laboratory diagnosis of cholera is bacteriological examination. Feces and vomit are used as material; feces are examined for vibrio carriage; From persons who died from cholera, a ligated section of the small intestine and gall bladder is taken.

When conducting a bacteriological study, three conditions must be observed: · culture material from the patient as quickly as possible (Vibrio cholerae persists in feces for a short period of time); · the containers in which the material is taken must not be disinfected chemicals and should not contain traces of them, since Vibrio cholera is very sensitive to them; · exclude the possibility of contamination and infection of others.

The material must be delivered to the laboratory within the first 3 hours; if this is not possible, use preservative media (alkaline peptone water, etc.).

The material is collected in individual vessels, washed from disinfectant solutions, at the bottom of which a smaller vessel or sheets of parchment paper are placed, disinfected by boiling. When shipping, the material is placed in a metal container and transported in a special vehicle with an accompanying person.

Each sample is provided with a label indicating the first and last name of the patient, the name of the sample, the place and time of collection, the intended diagnosis and the name of the person who took the material. In the laboratory, the material is inoculated onto liquid and solid nutrient media to isolate and identify a pure culture.

The results of the express analysis are obtained after 2-6 hours (indicative answer), the accelerated analysis - after 8-22 hours (preliminary answer), the full analysis - after 36 hours (final answer).

Serological methods are of auxiliary value and can be used mainly for retrospective diagnosis. For this purpose, microagglutination in phase contrast, RNGA, can be used, but it is better to determine the titer of vibriocidal antibodies or antitoxins (cholerogen antibodies are determined by ELISA or immunofluorescent method).

Differential diagnosis

Differential diagnosis is carried out with other infections that cause diarrhea. Differential characteristics are given in table. 17-11.

Table 17-11. Differential diagnosis of cholera

An example of a diagnosis formulation

A 00.1. Cholera (coproculture of Vibrio eltor), severe course, third degree dehydration.

Indications for hospitalization

All patients with cholera or suspected of having it are subject to mandatory hospitalization.

Treatment of cholera

Mode. Diet for cholera

No special diet is required for cholera patients.

Drug therapy

Basic principles of therapy: · replacement of fluid loss and restoration of the electrolyte composition of the body; · impact on the pathogen.

Treatment must begin within the first hours of the onset of the disease.

Pathogenetic agents

Therapy includes primary rehydration (replacement of water and salt losses before treatment) and corrective compensatory rehydration (correction of ongoing losses of water and electrolytes). Rehydration is seen as resuscitation event. In the emergency room, during the first 5 minutes, it is necessary to measure the patient’s pulse rate, blood pressure, body weight, take blood to determine hematocrit or relative density of blood plasma, electrolyte content, acid-base status, coagulogram, and then begin injecting saline solutions.

The volume of solutions administered to adults is calculated using the following formulas.

Cohen's formula: V = 4 (or 5) × P × (Ht 6 – Htн), where V is the determined fluid deficit (ml); P - patient’s body weight (kg); Ht 6 - patient's hematocrit; Htн - normal hematocrit; 4 is the coefficient for a hematocrit difference of up to 15, and 5 for a difference of more than 15.

Phillips formula: V = 4(8) × 1000 × P × (X – 1.024), where V is the determined fluid deficit (ml); P - patient’s body weight (kg); X is the relative density of the patient’s plasma; 4 is the coefficient for a patient’s plasma density up to 1.040, and 8 for a density above 1.041.

In practice, the degree of dehydration and, accordingly, the percentage of body weight loss are usually determined according to the criteria presented above. The resulting figure is multiplied by body weight to obtain the volume of fluid loss. For example, body weight 70 kg, degree III dehydration (8%). Therefore, the volume of losses is 70,000 g 0.08 = 5600 g (ml).

Polyionic solutions, preheated to 38–40 °C, are administered intravenously at a rate of 80–120 ml/min at II–IV degree of dehydration. Various polyionic solutions are used for treatment. The most physiological are Trisol® (5 g sodium chloride, 4 g sodium bicarbonate and 1 g potassium chloride); acesol® (5 g sodium chloride, 2 g sodium acetate, 1 g potassium chloride per 1 liter of pyrogen-free water); Chlosol® (4.75 g sodium chloride, 3.6 g sodium acetate and 1.5 g potassium chloride per 1 liter of pyrogen-free water) and Laktasol® solution (6.1 g sodium chloride, 3.4 g sodium lactate, 0. 3 g sodium bicarbonate, 0.3 g potassium chloride, 0.16 g calcium chloride and 0.1 g magnesium chloride per 1 liter of pyrogen-free water).

Jet primary rehydration is carried out using catheterization of central or peripheral veins. After replenishing losses, increasing blood pressure to physiological norms, restoring diuresis, and stopping seizures, the infusion rate is reduced to the required level to compensate for continuing losses. The administration of solutions is crucial in the treatment of seriously ill patients. As a rule, 15–25 minutes after the start of administration, pulse and blood pressure begin to be determined, and after 30–45 minutes, shortness of breath disappears, cyanosis decreases, lips become warmer, and a voice appears. After 4–6 hours, the patient’s condition improves significantly, and he begins to drink on his own. Every 2 hours it is necessary to monitor the patient’s blood hematocrit (or relative density of blood plasma), as well as the content of blood electrolytes to correct infusion therapy.

It is a mistake to administer large amounts of 5% glucose® solution: this not only does not eliminate the deficiency of electrolytes, but, on the contrary, reduces their concentration in the plasma. Blood transfusions and blood substitutes are also not indicated. It is unacceptable to use colloidal solutions for rehydration therapy, as they contribute to the development of intracellular dehydration, acute renal failure and shock lung syndrome.

Oral rehydration is necessary for cholera patients who are not vomiting.

The WHO Expert Committee recommends the following composition: 3.5 g of sodium chloride, 2.5 g of sodium bicarbonate, 1.5 g of potassium chloride, 20 g of glucose, 1 liter of boiled water (oralite solution). The addition of glucose® promotes the absorption of sodium and water in the intestines. WHO experts have also proposed another rehydration solution, in which bicarbonate is replaced by a more stable sodium citrate (Rehydron®).

In Russia, a drug glucosolan® has been developed, which is identical to the WHO glucose-saline solution.

Water-salt therapy is stopped after the appearance of fecal stools in the absence of vomiting and the predominance of the amount of urine over the amount of feces in the last 6-12 hours.

Etiotropic therapy

Antibiotics are an additional means of therapy; they do not affect the survival of patients, but shorten the duration of clinical manifestations of cholera and speed up the cleansing of the pathogen from the body. Recommended drugs and regimens for their use are presented in table. 17-12, 17-13. Use one of the listed drugs.

Table 17-12. Schemes of a five-day course of antibacterial drugs for the treatment of patients with cholera (I–II degree of dehydration, no vomiting) in tablet form

Table 17-13. Schemes for a 5-day course of antibacterial drugs for the treatment of patients with cholera (presence of vomiting, III–IV degree of dehydration), intravenous administration

Clinical examination

Patients with cholera (vibrio carriers) are discharged after their recovery, completion of rehydration and etiotropic therapy and receipt of three negative results of bacteriological examination.

After being discharged from hospitals, those who have suffered from cholera or vibrio carriage are allowed to work (study), regardless of their profession, they are registered with the territorial departments of epidemiological surveillance and clinical health clinics at their place of residence. Dispensary observation is carried out for 3 months.

Those who have had cholera are subject to bacteriological examination for cholera: in the first month, bacteriological examination of stool is carried out once every 10 days, then once a month.

If vibrio carriage is detected in convalescents, they are hospitalized for treatment in an infectious diseases hospital, after which dispensary observation of them is resumed.

Those who have had cholera or are vibrio carriers are removed from the dispensary registration if cholera vibrios are not isolated during the dispensary observation.

Its peculiarity is the change of pathogen from true cholera classic to Vibrio El Tor, characterized by a relatively benign course of the disease with a high frequency of vibrio carriage. Currently, cholera diseases are registered in dozens of third world countries, from where this infection is annually imported into economically more developed countries, including Russia.

Etiology

Pathogenesis

Epidemiology

Clinic

The atypical form can occur as erased, “dry” and fulminant cholera. The typical form of cholera develops acutely - loose, watery stools appear, without tenesmus and abdominal pain, but with rumbling and a feeling of fullness in the intestines.

Body temperature is normal, sometimes low-grade fever is possible. On examination, dryness of the tongue and mucous membranes is revealed.

The abdomen is painless, rumbling is detected along the intestines. Diarrhea lasts 1-2 days and if the course is favorable, recovery occurs.

As the disease progresses, the frequency of stools can increase up to 20 times a day. The stool is watery in nature, in typical cases it looks like rice water.

There are also completely transparent or slightly bile-stained watery stools. The addition of repeated “gushing” vomiting significantly worsens the patient’s condition.

The volume of each portion of pathological stool and vomit is on average 250-300 ml and varies little from bowel movement to bowel movement. Dehydration and demineralization of the patient's body develops.

There are 4 degrees of dehydration: Dehydration I degree - loss of fluid in the amount of 1-3% of body weight. The condition of patients during this period suffers little.

The main complaint is thirst. Dehydration of the second degree - loss of 4-6% of body weight is characterized by a moderate decrease in the volume of circulating plasma.

This is accompanied by increased thirst, weakness, dry mucous membranes, tachycardia, and a tendency to decrease systolic blood pressure and diuresis. Dehydration of the third degree is characterized by a loss of 7-9% of body weight.

At the same time, the volume of circulating plasma and intercellular fluid decreases significantly, renal blood flow is disrupted, and metabolic disorders appear: acidosis with accumulation of lactic acid. Cramps of the calf muscles, feet and hands occur, skin turgor is reduced, tachycardia, hoarseness, cyanosis.

Due to severe dehydration, facial features become sharpened, eyes become sunken, the “symptom of dark glasses”, “fades cholerica” is noted, and wrinkling of the skin of the hands determines the symptom of “washerwoman’s hands”. Hypotension, hypokalemia, acidosis, oliguria, characteristic of stage III dehydration, can be relieved with adequate therapy.

In its absence, IV degree of dehydration (loss of more than 10% of body weight) leads to the development of deep dehydration shock. Body temperature drops below normal (cholera algid), shortness of breath increases, aphonia, severe hypotension, anuria, and muscle fibrillations appear.

Decompensated metabolic acidosis and signs of severe tissue hypoxia develop. The latter include impaired consciousness in some patients, up to cerebral coma, and paralysis of the respiratory center, leading to asphyxia.

Only emergency prehospital and hospital therapy can save the patient. An even more rapid development of dehydration is possible.

In cases where dehydration shock develops within several hours (one day), the form of the disease is called fulminant. Dry cholera occurs without diarrhea and vomiting, but with signs of rapid development of dehydration shock - a sharp drop in blood pressure, the development of tachypnea, shortness of breath, aphonia, anuria, and convulsions.

In children, cholera often takes on a rapidly progressive course with the development of decompensated dehydration, anuria and signs of encephalopathy.

Differential diagnosis

In addition, patients with salmonellosis have symptoms of intoxication ( headache, fever with chills, nausea) precede vomiting and diarrhea or occur simultaneously with them. Cholera most often begins with diarrhea, followed by vomiting and the rapid development of dehydration. With salmonellosis, uncolored stools are rarely observed, stools are usually less frequent than with cholera, and there is an admixture of mucus in the stool. During sigmoidoscopy in patients with salmonellosis, focal changes mucous membrane (point hemorrhages, erosions), while with cholera, catarrhal changes in the mucous membrane of the colon are diffuse.

Hepatolienal syndrome is often observed in patients with salmonellosis. Due to the peculiarities of the course of El Tor cholera, there is a need to differentiate it from acute dysentery, especially caused by Shigella Sonne. Dysentery is characterized by scanty stool mixed with mucus and blood, tenesmus, abdominal pain, chills, and increased body temperature. During sigmoidoscopy it is determined various shapes proctosigmoiditis.

Severe symptoms of dehydration and impaired renal function are not typical. The greatest difficulties for differential diagnosis with cholera represent cases of rotavirus gastroenteritis. Both diseases begin with diarrhea and vomiting, but unlike cholera, with rotavirus gastroenteritis, abdominal pain is more intense, defecation is accompanied by loud rumbling, stool is profuse, foamy, bright yellow in color with a pungent odor. Important differential diagnostic symptoms are granularity, hyperemia, and swelling of the mucous membrane of the soft palate, which are detected in almost all patients.

The phenomena of dehydration characteristic of cholera are extremely rarely observed in patients with rotavirus gastroenteritis. While patients with cholera often experience tachycardia at the onset of the disease, rotavirus gastroenteritis is characterized by bradycardia. The most likely airborne mechanism of infection is rotavirus gastroenteritis, as evidenced by the concentration of diseases in close proximity to sources of infection. Mushroom poisoning (toadstool) causes a picture similar to a very severe form of cholera, but it is characterized by severe abdominal pain and the development of jaundice.

Anamnestic data and the absence of indications of a connection with the source of cholera infection allow us to doubt the diagnosis of cholera, and then reject it. The diagnosis of the first cases of cholera is of particular importance, since the official registration of cholera entails, in addition to medical measures, the introduction of restrictive measures in a given territory. Thus, with any combination of clinical and epidemiological data, the final diagnosis of the first cases of cholera must necessarily be confirmed by isolation of the pathogen from patients. At the same time, with an already developed epidemic, the mildest intestinal disease should be regarded as suspicious for cholera, and the patient must be subject to provisional hospitalization.

The specified approach and diagnostic tactics during an epidemiological outbreak of cholera are implemented through active identification of patients during door-to-door (door-to-door) and provisional hospitalization.

Prevention

Diagnostics

Treatment

The basic principle of treating cholera patients is immediate rehydration upon first contact with the patient at home, in an ambulance and in a hospital. For mild to moderate cases, oral rehydration should be performed.

The WHO Expert Committee recommends the following composition for oral rehydration: sodium chloride - 3.5 g, sodium bicarbonate - 2.5 g, potassium chloride - 1.5 g, glucose - 20 g, boiled water - 1 l. In Russia, this solution is more often called “Oralit”.

The addition of glucose promotes the absorption of sodium and water in the intestines. WHO recommends the use of a standard glucose-saline solution for oral rehydration for many acute intestinal infections, regardless of the etiology and age of the patients.

WHO experts have also proposed another rehydration solution, in which bicarbonate is replaced by a more stable sodium citrate (“re-hydron”). In Russia, a drug called citroglucosolan has been developed, which is identical to the WHO glucose-saline solution.

If it is impossible to accurately account for fluid losses with vomit and feces, it is recommended that children drink 50-150 ml of glucose-saline solution after each bowel movement (at a rate of 1 teaspoon - 1 dessert spoon per 1 minute), adults 200-250 ml (1 tablespoon in 1 minute). Along with the glucose-saline solution, an additional volume of plain boiled water, tea, rosehip decoction and other liquids is recommended.

Patients, and especially children, with frequent bowel movements in an unfavorable cholera situation should be examined every 12 hours or daily due to the possible rapid progression of the disease. In situations where observation is impossible, provisional hospitalization is indicated.

This is especially important in cases where during the first 6 hours oral fluid intake is ineffective and dehydration occurs. Often, such patients should immediately, starting from the prehospital stage, be given intravenous electrolyte solutions.

The calculation of the necessary solutions for rehydration in children depends on the child’s body weight and the degree of dehydration. In adults, oral rehydration fluid is calculated based on fluid loss in stool.

Oral rehydration is continued until diarrhea completely subsides. In case of severe cholera and in the presence of vomiting, polyionic solutions are administered intravenously: trisol, disol, acesol, quartasol, lactasol.

More often than others, trisol (Phillips solution No. 1) is used, containing sodium chloride 5 g, sodium bicarbonate 4 g, potassium chloride 1 g per 1 liter of pyrogen-free double-distilled water (5-4-1). If they are absent, Ringer's solution is used first.

Attention! The described treatment does not guarantee a positive result. For more reliable information, ALWAYS consult a specialist.

Cholera is a particularly dangerous, acute anthroponotic infectious disease of bacterial nature, characterized by epidemic prevalence and causing massive loss of fluid with rapid dehydration and high risk mortality in the absence of adequate treatment. Refers to highly dangerous, difficult to control quarantine infections.

The very name “cholera” means “gutter” and “bile flow”; these concepts came from ancient doctors, because they considered the cause of this disease to be “excessive flow of bile, as a result of which water flows from the body as if through a gutter.” India is considered the cradle of the infection. The epidemic situation became a little better after the genome of Vibrio cholerae was deciphered and dangerous sections of genetic information were eliminated from there - thus a vaccine was created in 2000.

The causative agent of cholera

The causative agent of cholera is the cholera vibrio Vibrio cholerae, or Vibrio El-Tor (the latter species causes the disease much more often). The causative agent of cholera is slightly curved, shaped like a comma. It has the following structure, which determines the characteristics of its life activity and the symptoms it causes:

It has 1 flagellum on its surface (that’s why it is called a monotrich), which determines its mobility;
Chemotaxis (purposeful movement towards nutrients) one of the factors that determines its movement;
Cholerogen exotoxin is a leading factor in determining symptoms. It consists of 2 subunits - A and B. “B” - it recognizes the intestinal cell (enterocyte) and establishes a connection with it by forming a connecting channel for the passage of subunit A; “A” - this part causes the release of salts and water from cells and intercellular substance into the intestinal lumen, by activating cascade chemical reactions, resulting in severe diarrhea with severe dehydration.
Enzymes (mucinase, protease, neurominidase, lecithinase) - destroying the intestinal mucosa, facilitating the penetration of the pathogen into the deeper layers of the intestinal mucosa;
To help the exotoxin and enzymes come pili - formations on the surface of the pathogen that resemble suction cups, which make its attachment to the enterocytes even stronger, this gives the pathogen a chance to multiply and colonize (fill) the intestines;
There is also endotoxin, but it is of more scientific importance than practical.

The cholera causative agent does not form capsules and spores, but despite this, it is quite stable in the external environment: high survival rate at low temperatures (ice and river water - 1 month, sea water - 1.5 months), in soil up to 3 months, in feces up to 3 days, in raw vegetables and fruits – up to 5 days. But the pathogen is less resistant to low temperatures (at 100° - instant death), also to drying, UV radiation and the action of disinfectants.

Regarding prevalence, it was believed that this indicator is high in endemic areas (natural foci): India, Bangladesh, Pakistan, Indonesia. But the sad experience of 2010 made us suspect widespread distribution, both geographically and bypassing age and gender restrictions. Outbreaks are characterized by summer-autumn seasonality, as favorable conditions are formed for the fecal-oral transmission mechanism of the pathogen.

Causes of cholera infection

The source is a sick person or carrier. Routes – water, food, contact and household. The predisposing factor is crowding and socialization of the population, as well as low acidity in the stomach.

Symptoms of cholera

There are a number of symptoms, the presence and severity of which depend on the severity of dehydration.

1st degree – manifested by a mild or erased clinic. At this degree, fluid loss = 1-3% of total body weight, due to vomiting and diarrhea up to 10 times a day, this fluid loss leads to dry mouth and thirst. Symptoms last up to 2 days.

Stage 2 – moderate degree, with a loss of 4-6% of total body weight, the frequency of vomiting and diarrhea up to 20 times a day, against the background of this, isolated cramps of the calf muscles/hands/feet/masticatory muscles develop. Cyanosis (cyanosis) of the nasolabial triangle also occurs (in this case, it is worth thinking about decompensation from the cardiovascular system, namely the right side of the heart).

3rd degree - severe degree of dehydration, accompanied by a loss of body weight by 7-9%, stool and vomiting more than 20 times per day and, as a result, symptoms of 1st and 2nd degrees worsen: thirst increases, the appearance of cyanosis on the extremities, convulsions become more extensive and painful, the voice is weak and barely audible. Due to the large loss of fluid, the turgor and elasticity of the skin decrease, and it becomes wrinkled (“washerwoman’s hand” symptom). A “Hippocrates mask” appears on the face - pointed features, sunken eyes. As a compensatory reaction, centralization of blood circulation occurs, that is, all blood from the periphery rushes to the internal organs and especially to the brain, and pallor of the skin is observed. But since centralization requires increased work of the heart, tachycardia (increased heart rate) and tachypnea (rapid breathing) occur.

Grade 4 is a very severe degree, which indicates an almost complete depletion of the body’s compensatory capabilities and extreme dehydration (literally in 12 hours, body weight loss decreases by 12%). This degree can be either a consequence of previous degrees or a separately occurring disease. But be that as it may, it proceeds the same way: a decrease in temperature to 34 ° C (therefore, this degree is often called “algid” - cold). There is shortness of breath, anuria (no urination - there is simply nothing left), hypovolemia (decrease in the volume of circulating blood, and as a manifestation of this - ↓ blood pressure). Stop vomiting and change it to convulsive hiccups. Stopping diarrhea and replacing it with free flow of intestinal fluid when pressing on the anterior abdominal wall (intestinal area). Rectal examination reveals a gaping anus. Ash-colored skin is the development of total cyanosis as a consequence of hypovolemia and impaired microcirculation.

Children under 3 years of age have some peculiarities of the course: due to the insufficient development of the compensatory reaction, they tolerate dehydration worse and the central nervous system suffers first of all: adynamia occurs (literally - lack of movement), clonic convulsions, impaired consciousness with the possible development of coma. Laboratory diagnostic difficulties also arise - in children it is impossible to rely on plasma density when determining the severity of dehydration, since they have a larger volume of extracellular fluid.

Features of symptoms at any degree:

Vomiting is not accompanied by nausea and is very profuse, which is why it is often called “fountain vomiting”;
Diarrhea in the form of rice water.

Diagnosis of cholera

1. Objectively, based on symptoms.
2. Bacteriological method - by inoculating the test material (feces and vomit) on nutrient media. Using this method, you can not only identify the pathogen, but also distinguish Vibrio cholerae from other species similar to it.
3. Serological method - blood serum is used and the reactions RIF (immunofluorescence reaction) and RNHA (indirect hemagglutination reaction) are performed - these two express methods are aimed at determining the antigen of Vibrio cholerae. ELISA (enzyme-linked immunosorbent assay) – determines the strength of the immune system.
4. Relative plasma density and hematocrit - their indicators will indicate the degree of dehydration.

Treatment of cholera

1. It is necessary to compensate for fluid and salt losses in accordance with the degree of dehydration (these indicators require laboratory specifications), therefore all patients must be hospitalized, since they undergo primary and corrective rehydration in the hospital. During treatment, the acid-base state and electrolyte levels are monitored to prevent overdose.

2. Etiotropic therapy (against the pathogen) - the use of antibiotics, and it is better to have a narrow spectrum, i.e. specifically against Vibrio cholerae (Polymyxin), but in some cases more is used wide range actions (ciprofloxacin, doxycycline, ofloxacin, etc.). The choice of antibiotic also depends on the degree of dehydration.

3. Prescription of general strengthening treatment in the form of prebiotics, probiotics, symbiotics, a complex immunoglobulin preparation (CIP) and vitamin complexes are possible.

There is no need for a specific diet or rehabilitation.

Complications of cholera

Due to disturbances in hemostasis and microcirculation, coronary insufficiency and as a result - myocardial infarction (impaired blood supply to the heart muscle), mesenteric thrombosis, acute brain failure, phlebitis. Cholera is deadly and can result in death if not treated promptly.

Preventing cholera

Specific: “cholera corpuscular inactivated vaccine” and chemical vaccines (mono- and bivalent). Vaccination is carried out according to epidemic indications. Non-specific: control and compliance with sanitary and epidemiological standards, control over water supply. Persons who have recovered from the disease are subject to 5-day observation and bacteriological examination 3 times. Contact patients are monitored using bacteriological testing and, as a preventive measure for the occurrence of the disease in contact patients, it is permissible to use antibiotics in prophylactic doses for 4 days.

General practitioner Shabanova I.E.

Cholera - English, French, Cholera asiatica - Latin, Colera - Spanish.
Cholera- an acute infectious disease characterized by varying degrees of dehydration due to damage to the small intestine, loss of fluid and salts and manifested by watery diarrhea and vomiting.

Cholera refers to quarantine (conventional) human diseases. It affects large groups of people in a short time, so it is considered a particularly dangerous infection.
Cholera brought untold disasters to humanity. Since ancient times, cholera has been endemic in the Ganges and Brahmaputra river basins in India and Bangladesh, from where it spread by sea, land and caravan routes throughout the world. From 1817 to 1926, there were 6 devastating cholera pandemics, each time sweeping Russia, claiming millions of human lives. All 6 pandemics were associated with Vibrio cholerae asiaticae. The onset of the 7th cholera pandemic in 1961 from the Indonesian Islands coincided with the emergence of a new variant of Vibrio cholerae, Vibrio cholerae eltor, which had long been considered non-pathogenic.

Feature of the 7th pandemic cholera there was an extremely rapid spread of it in many countries where cholera had not existed for a long time or was not recorded at all. By 1965, cholera reached Afghanistan and Iran, and was introduced to Uzbekistan (Khorezm region) and Karakalpakstan. In 1970, large epidemic outbreaks of cholera occurred on the territory of the USSR in a number of cities in the Black Sea and Caspian basins (Odessa, Kerch, Astrakhan, etc.). According to WHO, by 1970, cholera affected 39 countries. Since then, there have been isolated cases of imported El Tor cholera. There are no endemic foci of it on the territory of Russia.

Pathogen cholera V. cholerae asiaticae was discovered by Robert Koch in 1883. Working in Egypt and India, he isolated comma-shaped vibrios cholerae (“Koch’s comma”) from the feces of patients and the intestinal contents of corpses. Information has appeared that Vibrio cholerae was discovered before Koch by F. Pacini (1853) and E. Niedzwiecki (1872). However, Koch has the honor of studying Vibrio and establishing its etiological role in cholera (1883). Later, in 1906, Gottschlich isolated hemolytic vibrio from the corpses of pilgrims (who died of dysentery?!) at the El Tor quarantine point (west coast of Sulawesi), the pathogenicity of which was not proven at that time.

It was not until 1939 that an outbreak was first described cholera, associated with this pathogen in Indonesia. In the 60s of the 20th century, it was finally recognized as the causative agent of cholera during its 7th pandemic. Thus, it was recognized that the classical Vibrio cholerae Koch and Vibrio cholerae El Tor are the true causative agents of cholera. In their basic morpho-biological properties they are identical. These are small, slightly curved rods, at one end of which there is a long flagellum that provides mobility, which is used to identify vibrio in laboratory diagnostics. They are gram-negative, stain well with aniline dyes and grow on ordinary weakly alkaline nutrient media; on peptone water they form a delicate surface film that is easily destroyed by shaking; they are aerobes, biochemically active, ferment many carbohydrates, starch, and when sowing, they liquefy gelatin in the form of a funnel along the injection.

Currently known more than 150 serovars of V. cholerae, which are divided into groups A and B. The true causative agents of cholera are included in group A (classical and Eltor). Vibrio Eltor has serovars: Ogawa, Inaba and Gikoshima, which differ in antigenic structure. Vibrios cholerae form toxic components: a thermostable lipoprotein complex (endotoxin), a thermolabile exotoxin (enterotoxin, cholerogens), which is the main component of the pathogen that triggers the pathogenetic mechanisms of dehydration and demineralization of the body, as well as a number of enzymes and low molecular weight metabolites. At the end of the 20th century, reports appeared about a new vibrio of a previously unknown serogroup O 139 (Bengal). This cholera pathogen was introduced to southern Russia in 1993.

Believe that the emergence of a new serovar Vibrio cholerae creates real threat epidemic situation similar to that observed at the beginning of the 7th cholera pandemic in 1961.

Bacteria, which are not agglutinated by cholera O-serum, are classified as NAG vibrios, which can cause diseases similar to cholera, but differing from it in a number of clinical features.

Vibrio cholerae preserve well at low temperatures and freezing. Boiling kills them within a minute. The pathogen is very sensitive to weak concentrations of hydrochloric acid (HCI at a dilution of 1:100,000 kills Vibrio in a few seconds) and other acids, as well as to disinfectants. When the residual chlorine content in water is 0.2-0.3 mg/l, the vibrio dies within a few minutes. In the water of shallow reservoirs, in silt, and in the bodies of hydrobionts (fish, amphibians) in the warm season, vibrios can reproduce. These vibrios differ from cholera pathogens isolated in epidemic foci by being less virulent and weakly pathogenic. It is assumed that under natural conditions an exchange of genetic information is possible between Vibrio strains isolated from patients and free-living Vibrios. The causative agent of cholera is sensitive to tetracyclines, chloramphenicol and fluoroquinolones.