home Thyroid Mechanism of infection in cholera. Cholera is a life-threatening disease. Severe cholera

Mechanism of infection in cholera. Cholera is a life-threatening disease. Severe cholera

Cholera- it's very dangerous bacterial infection, which is usually transmitted through contaminated water.

Cholera causes severe diarrhea and dehydration.

If left untreated, cholera can lead to death within a few hours or days.

Modern wastewater treatment methods have virtually eradicated cholera from developed countries. In the United States, the last major outbreak was recorded in 1911. But cholera still causes epidemics in Asia, Africa, Latin America, the Middle East and India. The risk of cholera is especially high among the poor, who live in crowded conditions without basic sanitation, as well as among refugees and victims of natural disasters.

Cholera is easy to treat if it is started on time. Death from cholera is usually the result of severe dehydration, which can be prevented with simple rehydration solutions.

Causes of cholera

Cholera is caused by a bacterium called Vibrio cholerae. Vibrio cholerae has two distinct life cycle- inside human body and beyond.

1. Vibrio cholerae in the environment.

This bacterium is natural conditions lives in coastal waters, where it attaches to small crustaceans and other organisms. Vibrio cholerae travels with its host as crustaceans migrate in search of food - algae. Algae grow intensively in warm coastal water, and urea, which is contained in wastewater, is especially conducive to their growth. This is why the risk of cholera increases during the warmer months, especially in areas contaminated by sewage.

2. Vibrio cholerae in the human body.

When a person ingests cholera bacteria, it can cause the disease itself, or it can simply multiply in the intestines and be excreted in the feces. When the feces of a cholera carrier get into drinking water or food, they become a dangerous source of infection.

The deadly effects of Vibrio cholerae on the body are associated with the powerful toxin CTX, which the bacterium secretes in the small intestine of the patient. CTX disrupts the normal flow of sodium and chloride in the intestinal wall. Because of this, it accumulates in the lumen a large number of water, watery diarrhea occurs and sudden loss liquids and electrolytes. Contaminated water supplies are a major risk factor for cholera. Eating raw fish, unpeeled fruits and vegetables can also lead to contracting this dangerous infection.

In order for a person to get sick, more than a million bacteria must enter the body - approximately the same amount contained in one glass of contaminated water. Therefore, cholera is rarely transmitted through contact with a sick person.

So, the main sources of cholera are:

Water from natural sources, wells. Vibrio cholerae can live in water bodies for a long time. Water is the main source of major cholera outbreaks. People living in unsanitary conditions are at greatest risk.
. Seafood. It is very risky to consume raw or poorly processed seafood, especially shellfish from certain unsafe waters. For example, US authorities strongly recommend carefully preparing seafood from the Gulf of Mexico.
. Raw fruits and vegetables. The source of infection is often raw, unpeeled fruits or vegetables. IN developing countries manure fertilizers and dirty water for irrigating fields can lead to crop contamination. Therefore, you need to be especially careful about vegetables and fruits from third world countries.

Risk factors for cholera.

Everyone is susceptible to cholera, with the exception of infants, who have received immunity from mothers who have had the disease.

But there are several factors that increase a person's susceptibility to cholera:

Low or zero acidity gastric juice. Vibrio cholerae cannot survive in acidic environment- the normal environment of gastric juice. It is the stomach that should serve as a barrier to infection, as provided by evolution. But people with low acidity, as well as those who take anti-ulcer medications (H2-histamine blockers, proton pump inhibitors, antacids) are at risk.
. Blood type 0. But for unknown reasons, people with blood type 0 are twice as susceptible to cholera as people with other groups.

Symptoms of cholera

Most people exposed to Vibrio cholerae do not get cholera. They do not even suspect that they have been infected. But these people become carriers, shedding bacteria in their stool within 7-14 days after infection. In most patients, cholera causes mild symptoms And moderate severity, so without laboratory tests sometimes it cannot be distinguished from banal food poisoning. Only one in 10 infected people develops the typical picture of cholera, with profuse watery diarrhea and rapid dehydration.

Symptoms of cholera include:

Diarrhea (diarrhea). With cholera, diarrhea occurs suddenly and can quickly lead to dehydration. IN severe cases a person loses up to 1 liter of fluid every hour. Feces have the appearance of water in which rice was washed - watery, whitish in color.
. Nausea and vomiting. These symptoms occur both early and late late stage diseases. Vomiting can exhaust the patient for several hours in a row.
. Dehydration (dehydration). Severe dehydration of the body develops during the first hours. The degree of dehydration depends on how much fluid the patient loses through stool and vomit, and how treatment is carried out. A loss of 10% of body weight corresponds to severe dehydration. Signs of dehydration in cholera are: irritability, drowsiness, thirst, sunken eyes, dry mouth, decreased skin turgor, reduced output urine, pressure drop, arrhythmia, etc.

Dehydration is dangerous sudden disruption balance minerals who play important role in organism. This condition is called electrolyte imbalance. He demands urgent treatment, otherwise the patient may die.

Symptoms of electrolyte imbalance:

Muscle spasms and impairment heart rate. As a result sudden loss chlorides, potassium and other substances disrupt muscle contractions, including heart muscle (arrhythmia).
. Shock. This is one of the most serious consequences dehydration. Shock occurs when insufficient circulating blood volume causes a drop in blood pressure. If help is not provided in time, hypovolemic shock leads to death within minutes.

The symptoms of cholera in children are generally similar to those in adult patients.

But in children the disease is more severe and they may experience the following symptoms:

Depression of consciousness, up to coma.
. High body temperature.
. Cramps.

When should you see a doctor?

The risk of cholera is very low in developed countries, and even in disadvantaged areas you are unlikely to get sick if you follow government advice and good hygiene. But sporadic cases of cholera still occur around the world. If you experience diarrhea after visiting a dangerous region, consult a doctor. If you have profuse, watery diarrhea and you suspect cholera, seek medical attention immediately. Remember that severe dehydration can develop within the first hours of illness. Don't waste time!

Diagnosis of cholera

IN dangerous areas Doctors initially suspect cholera, so most likely there will be no problems with making a diagnosis. But in parts of the world where cholera is rarely found, it may take time for doctors to make a correct diagnosis.

Today it is not necessary to do a culture and wait to confirm this or that infection. In developed countries, special rapid tests are used to quickly identify cholera. Rapid diagnosis reduces mortality and helps prevent cholera outbreaks through timely intervention.

Treatment of cholera

Cholera requires immediate treatment.

Treatment methods are as follows:

Rehydration. The main task is to restore lost water and electrolytes. To do this, use simple salt solutions, such as widely famous drug Regidron. These products are sold in powder form, which are dissolved in water and taken in portions at certain intervals. In severe cases, the doctor may prescribe intravenous administration special solutions. With proper rehydration, the mortality rate from cholera does not exceed 1%.
. Antibiotics. Surprisingly, antibiotics are not a major part of cholera treatment. In some cases, the antibiotic doxycycline (Doxibene, Unidox) or azithromycin (Sumamed) is actually prescribed. The dosage and duration of treatment is determined only by the doctor.
. Zinc preparations. Recent studies have shown that zinc may shorten the duration of diarrhea in children with cholera.

Complications of cholera

Cholera can quickly lead to fatal outcome. In the most severe cases, this occurs within 2-3 hours, sometimes before the person is taken to the hospital. In other cases, death from dehydration may occur within a few days from the onset of the first symptoms.

In addition to the shock and severe dehydration mentioned above, cholera can cause the following complications:

Hypoglycemia ( reduced level blood sugar). If a person becomes so weak that they are unable to even eat, hypoglycemia may occur. Deficiency of sugar, main nutrient cells, causes convulsions, loss of consciousness, and even death. The risk of such complications is highest in children.
. Hypokalemia (low potassium levels). Cholera patients lose enormous amounts of electrolytes, including potassium. Very low potassium levels impair nerve function, cause arrhythmias, and can be life-threatening.
. Kidney failure. When the kidneys' filtering capacity is impaired, excess toxins and some electrolytes accumulate in the body. This condition can lead to death. In cholera patients, kidney failure is often combined with hypovolemic shock.

Konstantin Mokanov

The twenty-first century is a time of new technologies and discoveries, including in the field of medicine. If earlier epidemics of diseases that wiped out entire families and localities brought fear and horror to people, today medical scientists have found ways to combat many previously incurable ailments. For example, the cholera epidemic in Russia in the nineteenth century claimed the lives of more than two million people. However, today the mortality rate from this disease is only 5-10%.

The biggest epidemics in human history

Epidemic is a mass spread of disease or infection. In the entire history of mankind, one can count a couple of dozen of the most terrible and dangerous epidemics.

The main reason for the global spread of infections is the lack of sanitary standards, lack of personal hygiene, development of new territories.

Cholera epidemic

Cholera is an intestinal infection that is accompanied by a sudden loss of fluid and dehydration. Caused by a bacterium. The method of transmission of the disease is household - through water, contaminated food. There are several strains of cholera, each of which is serious in its own way. For example, Nepalese cholera, which does not cause much harm to local residents, has become deadly dangerous virus for the population of the Dominican Republic and Haiti.

The largest outbreaks of the epidemic have been recorded in Africa, Latin America, and India. And although modern treatment methods make it possible to cope with this disease, the mortality rate is still 5-10%. In Russia, the cholera epidemic of 1830 was the first large-scale manifestation of an infection of this type. Combined with the plague, it took the lives of millions of people.

You can protect yourself and your loved ones from cholera by following the rules of personal hygiene. People who often travel around the country and abroad should be especially attentive to their health. You should always avoid questionable eateries and cafeterias. And buy food not in spontaneous markets, but in specialized places. When visiting foreign countries, it is better to get vaccinated.

Three forms of cholera

Cholera is infection, which affects the intestines and kidneys. The disease can occur in the human body in three forms, depending on the degree of dehydration.

Easy. The main symptoms are diarrhea, sometimes slight vomiting, and discomfort in the abdominal area. The urge to go to the toilet can reach up to five times a day. General health patient - satisfactory.
Medium shape. Symptoms are diarrhea (up to ten times a day) and vomiting, which are increasing. The patient is constantly tormented by thirst and dry mouth. Minor cramps of the muscles, feet, and fingers may be observed.
Severe form. Cholera disease at this stage often has death. Symptoms: profuse bowel movements, up to twenty times a day, repeated vomiting, thirst, dry mouth, hoarse voice. The body becomes dehydrated, the person acquires characteristic appearance- pointed face, wrinkled hands, sunken eyes. Lips, ears, skin become bluish. This is how cyanosis develops. Urination occurs less frequently and soon stops altogether.

Children suffer the most from cholera. This is because their body has not yet learned to cope with the unusual loss of fluid.

The best prevention of cholera is personal hygiene. At the slightest symptoms indicating this disease, you should immediately contact the hospital for qualified help.

How to recognize cholera?

This disease is often confused with others similar diseases, for example, with food poisoning, which has similar symptoms. And poisoning, as a rule, most people treat on their own. As a result, treatment is carried out with the wrong drugs, and during this time the disease itself can acquire a more severe form.

Therefore, every person should know what cholera is, what its symptoms are and how to fight it. So, the main signs of the disease:

Diarrhea from five to ten or more times a day. The amount of bowel movements gradually increases and can reach up to one and a half liters at a time!
There is no pain as with poisoning.
Vomiting is increasing in nature. No nausea is observed. The vomited liquid resembles rice cereal.
Rapid dehydration of the body. The skin takes on a bluish color. A man is being tortured constant thirst, dry mouth. What cholera looks like (photos of patients) can be seen in scientific brochures and encyclopedias (and a little in this article).
Muscle cramps.

First aid for cholera

If someone close to you experiences all the symptoms of cholera, you should immediately consult a doctor. The patient must be hospitalized immediately. However, there are situations when you get medical care It doesn’t work out that quickly (staying outside populated areas). In this case, everyone should know how to provide first aid.

The main rule is more liquid. How much the body loses, how much you need to try to “pour in.” It is recommended to drink 200 ml every half hour. But it should not be just water, but a special solution (per liter of water - a teaspoon of salt and four teaspoons of sugar).

Particular attention should be paid to feces and their disinfection. Ducks and personal care products should be carefully treated to prevent the spread of infection. Bedding needs to be changed frequently. Wash the patient's clothes at 90 degrees. It is advisable to iron them after washing.

Such precautions are mandatory, because it is not difficult to become infected at home.

Etiology and epidemiology of cholera

One of the terrible and incurable diseases of past centuries is cholera. Photos of bacteria taken under a microscope make it clear that the pathogen has the appearance of a curved rod with one or two strands arranged in polar directions, which help it move.

The microbes that cause cholera are lovers of alkaline environments. They are able to decompose starch and carbohydrates, as well as liquefy gelatin. The causative agent of the infection is sensitive to drying and exposure to ultraviolet rays. When boiling, microorganisms die instantly.

Since cholera is caused by a bacterium that can be found in food and water, the best prevention there will be proper food processing.

If the infection enters drinking water sources, it can affect entire settlements. We are talking about an epidemic. And when the disease has already spread beyond the boundaries of one territory or an entire country, then a pandemic has already occurred. Cholera is a disease, an epidemic, and a pandemic.

Diagnosis and treatment

Of course, you cannot diagnose cholera on your own. Symptoms of the disease alone are not enough. Medical examinations are required, which are carried out in special bacteriological laboratories. For research, the patient's secretions are required - vomit, feces.

If you delve deeper into history, the cholera epidemic of 1830 in Russia took more than one life. Everything can be explained by the insufficiently strong medicine of that time. Today, the disease is treatable. To do this, it is enough to make timely diagnosis and therapy.

We must remember that cholera is an epidemic. It can affect several family members at once. Any suspicious symptoms should be a reason to go to the hospital. Incubation period cholera infection ranges from several hours to five days. At this time, patients are already carriers of the infection and release the pathogen into the external environment.

Treatment of the disease is carried out only in hospitals, in special infectious diseases departments. The main task of doctors is to replenish and support water balance in the patient's body. For this purpose, saline solutions and medications are used.

The most common bacteria that cause cholera are the classical biotype and El Tor cholera. Both species are sensitive to antibiotics. Therefore, treatment also includes the use of antibacterial drugs. Erythromycin is usually used.

The best protection against cholera in our time is vaccination. The vaccine is administered twice a month. Doses depend on the patient's age.

Preventing cholera

Cholera, like any disease, is better prevented than treated. To do this, it is enough to follow all the precautions that are used to prevent acute intestinal infections.

Cholera bacteria can be found in food and water. Therefore, you should never drink water from questionable sources. IN extreme cases it should be boiled.
Vegetables, fruits, fish, meat and other raw foods must be thoroughly processed before consumption.
You cannot swim in reservoirs where there are prohibitions from the sanitary and epidemiological station. Perhaps the water contains cholera or some other disease.
Patients with signs of cholera should be immediately hospitalized, and the room where they were located should be disinfected.
When visiting other countries, it is better to get vaccinated. Of course, vaccination cannot provide one hundred percent protection, but in the event of an epidemic, it will be easier for the vaccinated body to cope with the disease.

It must also be remembered that even after complete recovery, cholera bacteria can infect the body a second time. Therefore, extra vigilance and caution will not hurt!

How does the disease manifest in children?

The disease develops in children exactly as it does in adults. However, children are more susceptible to infection.

Most often, infection occurs through water or food. But in the case of children, infection through close contact - through dirty hands - cannot be ruled out.

Cholera bacteria, entering a child’s body, cause severe intoxication and diarrhea. The development of the disease leads to impaired kidney function (nephropathy), cardiac arrhythmia, and pulmonary edema. Some children develop seizures and coma. Therefore, early diagnosis of the disease is simply necessary. In such cases, cholera disease is curable in almost one hundred percent of cases.

Treatment of sick children, like adults, is carried out only inpatiently. Therapy is aimed at replenishing lost fluid. Patients with severe form fluid is administered intravenously.

Caring for the patient also includes thorough disinfection of household items and excrement.

Do not forget about the full and healthy eating. After all, during illness a person loses a lot of fluid, and at the same time weight.

The best prevention of cholera in children is to teach them to always and everywhere wash their hands, food and drink only boiled water. This is especially important when visiting a child kindergarten or schools.

Conclusion

The development of medicine and science in our time has provided a solution for the treatment of many dangerous diseases. For example, plague and smallpox have become conventional diseases, since the vaccine completely eradicated them from our lives. The disease cholera, in contrast, is still relevant in some parts of the Earth. However, found effective methods therapy for this disease. It is enough just to ask for help in time.

The largest outbreaks of the epidemic are recorded in remote areas of Africa, Asia, and India. The main reason is polluted water, lack of sanitary standards, poverty and destitution. For many residents of those countries, the concept of “hospital” is unfamiliar. In such cases, diagnosis of cholera and first emergency aid can be carried out independently (though not always successfully).

Cholera is an acute intestinal infection, the peculiarity of which is that it primarily affects the small intestine. The disease is accompanied by a violation of water-salt metabolism with varying degrees severity of dehydration. This occurs due to massive loss of fluid through vomiting and copious watery stools. The disease is considered a particularly dangerous infection and can quickly spread throughout the population.

Symptoms of cholera development

The incubation period for cholera can range from several hours to 5 days, but on average it is 2–3 days. If a person took antibiotics prophylactically, but still fell ill, the incubation period can extend to 9-10 days.

The disease is characterized by a sudden onset. The most pronounced manifestation cholera is diarrhea that appears first. The stool characteristic of cholera looks like a watery, cloudy-white liquid with flakes floating in it. The chair is similar in appearance like rice water and has no odor.

One of the first symptoms of cholera is also muscle weakness and cramps in the area. calf muscles. Subsequently, loose, watery stools are accompanied by profuse, frequent vomiting. Loss of fluid with diarrhea and vomiting leads to severe dehydration of the body, as a result of which the patient’s appearance changes: facial features become sharper, the skin acquires a bluish tint, and easily folds.

Severity of cholera

Cholera has several degrees of severity and stages of dehydration.

I degree of severity. At this degree, body weight loss occurs in the range of 1–3%. Diarrhea and vomiting become more frequent from 2-3 to 5-6 times a day, and the duration of these disorders is 1-3 days. The patient's well-being usually suffers little. The patient may feel slight general weakness, thirst, and dry mouth. Coloring skin and mucous membranes does not change, pulse rate, blood pressure, urination remain within normal limits.

II degree characterizes body weight deficiency in the range of 4–6%. Stools become more frequent up to 15–20 or more times a day, sometimes slight pain appears in the epigastric region, diarrhea is accompanied by frequent vomiting. With the symptoms of cholera, general and muscle weakness, dry skin and mucous membranes become more pronounced, the tongue is dry and appears on it. white coating. There is constant cyanosis of the lips and mucous membranes, hoarseness and roughness of the voice. In rare cases, there may be short-term cramps of the masticatory muscles and muscles of the feet, hands and legs. In many patients, tachycardia is registered, blood pressure decreases, and the volume of urine excreted decreases.

Underweight at III degree of severity of cholera is already 7–9%. Bowel movements may become more frequent up to 25–35 times a day or more, and vomiting may occur repeatedly. This degree is characterized by

severe general weakness,
indomitable thirst.
Muscle cramps in the limbs and abdomen become frequent and painful.
The skin and mucous membranes with cholera symptoms are constantly cyanotic.
The skin is cold to the touch.
The patient's voice is hoarse, almost silent.
Body temperature can drop to 35.5°C.
There has been a sharp decline blood pressure, tachycardia, shortness of breath, patients almost completely stop urinating.
Noteworthy are the sharpening of facial features, sunken cheeks and eyes.

At IV degree cholera and dehydration, a loss of over 10% of body weight occurs. Characterized by the rapid development of signs of cholera with very frequent diarrhea and vomiting. The condition of the patients is extremely serious. Cholera symptoms reach their maximum severity. Facial features become sharpened, cyanosis of the skin and mucous membranes is widespread, the skin is cold to the touch and covered with sticky sweat. There is pronounced cyanosis around the eyes, “washerwoman’s hands”, a pained expression on the face. Cramps of all muscle groups develop, they are often repeated and very painful. Body temperature drops to less than 35°C, voice is completely absent. Job of cardio-vascular system with symptoms of cholera, it is sharply disrupted: tachycardia, muffled heart sounds, pulse and blood pressure can no longer be detected, rapid, shallow breathing.

Sources of cholera

Cholera is caused by Vibrio cholerae. There are two main ones - the classic one, which causes Asian cholera and El Tor.

The main route of infection with cholera is waterborne, when unboiled water from open reservoirs is consumed.

After passing through the stomach, the vibrio enters small intestine, where it colonizes and multiplies on the surface of the intestinal epithelium. However, in sick people, vibrio can be found in any part of the body. gastrointestinal tract. Having reached a certain concentration during reproduction, vibrio causes disease.

As the disease develops, a huge amount of fluid and salts of sodium, potassium, chlorides and bicarbonates are lost. Vibrio cholerae affects people of all ages. The disease is most severe in people who abuse alcohol, who have undergone surgery to remove part of the stomach, and in young children.

Provoking factors for cholera disease

The disease usually occurs in the summer-autumn period. This is facilitated by

drinking large amounts of water,

abundance of flies,

lots of fruits and vegetables.

Particular caution should be exercised by those planning to visit regions where cholera is very common. These are India, Latin American countries, Egypt, Indonesia, Uzbekistan, sea cities Ukraine.

In Russia, foci of cholera disease exist in Astrakhan and the Caucasus (cholera is the only intestinal infection that is a quarantine disease). Infection with cholera usually occurs through the use of contaminated water (including when washing dishes, fruit, etc.) or through the consumption of foods contaminated with cholera bacteria and through dirty hands.

Infectious diseases lecture 4

TOPIC: CHOLERA.

Cholera is an acute anthroponotic intestinal infection caused by Vibrio cholerae and characterized by watery diarrhea followed by vomiting, the development of dehydration, demineralization and acidosis.

Even before our era, the characteristic signs of this disease were described, indicating rapid spread and high mortality.

At the beginning of the 19th century, when international communications became widespread, cholera turned from an endemic disease South-East Asia into epidemic, pandemic pathology.

From 1817 to 1926, 4.5 million people around the world suffered from cholera, of which 2 million died from cholera.

In Russia during this time, significant outbreaks of cholera occurred 8 times. P.I. Tchaikovsky died of cholera.

The Italian Pacini was the first to describe the causative agent of the disease and, independently of him, the doctor Nedzvetsky.

The most significant contribution to the study of the pathogen was made by Robert Koch. He isolated the pathogen in pure culture, described its properties, and recommended media for growing vibrio. In 1906, the German scientist Friedrich Gottlieb at the El Tor quarantine station (Sinai Peninsula) isolated the second causative agent of cholera - the El Tor vibrio.

We are currently experiencing the seventh cholera pandemic. There was a change in pathogen from classical vibrio to vibrio El Tor. In this case, the disease proceeds relatively benignly. The proportion of deaths has decreased.

Another feature of the latest pandemic is that vibrio carriage often remains. Registered on all continents. The maximum incidence in recent years is in the countries of Central and South America. Cholera outbreaks have spread over time - the period of increased incidence has become longer and is slowly declining; there are no peaks in incidence.

ETIOLOGICAL CHARACTERISTICS OF THE CAUSE OF CHOLERA.

There are two types of pathogens: classic cholera vibrio (cholera biotype), and cholera vibrio El Tor biotype. They differ in biochemical properties.

Morphology: curved rod with a rather long flagellum. They do not form spores or capsules. Gr (-), stain well with aniline dyes. Can form L-forms.

Growth characteristics: obligate aerobes, optimal environment - alkaline (pH 7.6 -9.0). On liquid media they grow in the form of a gray or bluish film. They are characterized by very rapid reproduction. Biochemical activity: can liquefy gelatin, decompose starch, reduce nitrates to nitrites. The most reliable biochemical criterion is Heiberg's triad.

The Heiberg triad is the ability of cholera vibrios to break down mannose and sucrose and the inability to ferment arabinose.

Antigenic structure: they have a flagellar H-antigen (common to all vibrios) and a somatic thermostable O-antigen. The causative agents of cholera belong to serogroup O-1.

Depending on the properties of the O-antigen, 3 serovars are distinguished: Agave, Inawa, Gikoshima.

There are NAG vibrios that are not agglutinated by O-1 serum. They can cause diarrheal diseases, but cholera is not diagnosed in this case. If the frequency of excretion of NAG vibrios increases significantly, this indicates an epidemic problem, pollution of water bodies by wastewater, and toxigenicity.

Vibrios secrete an exotoxin - cholerogens - the most important pathogenetic factor. When microbial bodies are destroyed, endotoxins are released.

The third component of toxicity is the permeability factor. These are groups of enzymes that help increase the permeability of the vascular wall, cell membranes and promote the action of cholerogens.

Sustainability in external environment high. In open water pools they last for several months; in wet feces they last up to 250 days. In direct sunlight they can last up to 8 hours.

Disinfectants quickly destroy vibrios (chlorine-containing preparations in concentrations of 0.2-03 mg/l). Heating to 56 degrees kills vibrios in 30 minutes, boiling instantly. Vibrios are sensitive to weak acid solutions and resistant to alkalis. Tetracycline and nitrofurans have a detrimental effect on vibrio.

Epidemiology of cholera .

This is anthroponosis. The source of infection is only people. Groups of vibrio carriers:

Patients with a typical form of cholera, the maximum release of vibrios during the course of the disease. The most dangerous form is severe, when there is severe enteritis and severe vomiting.

Patients with subclinical or erased form of cholera. The clinical picture is insignificant, but the release of the pathogen and the spread of infection are significant.

Convalescents after a typical or subclinical form of cholera - vibration excretors - convalescents. There are no longer any clinical signs, but the release of the pathogen continues for a long time.

Transient healthy carriage. The disease does not develop, but pathogens can be detected in feces for a long time. More typical for El Tor.

The mechanism of infection is fecal-oral.

Distribution routes: water, alimentary, contact and household. Most frequent path infection - water (drinking, washing vegetables, fruits, vegetables, bathing). Infection of shellfish, fish, shrimp, and frogs should be noted. In these organisms, the vibrio persists for a long time. Eating them without heat treatment increases the risk of developing the disease.

Seasonality: summer-autumn. During this period, more fluids and bathing are consumed. Increased fluid intake also leads to a decrease in the concentration of hydrochloric acid in gastric juice.

Receptivity is universal and high. In endemic areas, it is mainly children and the elderly who are affected. When an infection is introduced into a new place, it is more often affected adult population(usually men aged 20-40 years).

Predisposing factors:

anacid gastritis

helminthic infestations

some forms of anemia

gastrectomy

precancerous conditions, etc.

Immunity is relatively stable, species-specific and antitoxic. Repeated cases of cholera are rare.

PATHOGENESIS.

Having penetrated through the mouth, some of the vibrios die in the stomach. If there are predisposing factors, increased fluid intake, then vibrios penetrate the intestines. There is an alkaline environment and a high content of peptones (many protein molecules and other nutrients). This contributes to the intensive reproduction of vibrios. The release of exotoxin and permeability factors leads to the main clinical manifestations.

Cholerogen is the trigger of the pathological process. The action of cholerogens is assisted by a permeability factor - enzymes such as neuraminidase. Neuraminidase breaks down glycoproteins. The membrane of enterocytes contains gangliosides G and M. The modification of this ganglioside and the very presence of cholerogens leads to the activation of the enzyme adenylate cyclase. This leads to increased synthesis of cAMP (the concentration in the enterocyte increases tens, hundreds of times) cAMP is a regulatory substance that changes fluid flows. Normally, the function of the enterocyte is to absorb fluid from the intestinal lumen into the cell. A high concentration of cAMP causes fluid from the cell to be secreted into the intestinal lumen. A study of intestinal juice in this case shows that 1 liter contains 5 g of table salt, 4 g of sodium bicarbonate and 1 g of potassium chloride. This ratio is very important for treatment. The ratio of electrolytes in 1 liter of intestinal juice 5 to 4 to 1 can be administered intravenously, or given orally along with sugars. Sugars promote the absorption of electrolytes. Since a lot of fluid is lost, hypovolemia develops (decrease in blood volume). Blood viscosity increases. Vascular insufficiency develops. Lack of oxygen in tissues. Due to lack of oxygen, metabolism is disrupted and acidosis develops. Subsequently, severe metabolic disorders can lead to necrosis renal tubules. Electrolytes leave with water. The most significant loss of potassium. Hypokalemia leads to the development of muscle weakness, and individual muscle groups can contract uncoordinatedly, which leads to the appearance of a convulsive syndrome.

PATHOLOGICAL ANATOMY.

The most detailed picture of pathological changes was described by Pirogov. Indicating that the muscles are in a state of pronounced rigor mortis N.K. Rosenberg described the syndrome of turning a corpse due to muscle tone(some muscles are relaxed, others are contracted). Wrinkling of the skin is characteristic - “washerwoman’s hand”. Convulsive muscle contraction leads to the posture of a boxer and fencer (muscles are clearly tense). At autopsy there is no pungent cadaveric odor. Rotting comes late. Subcutaneous tissue is dense. The blood vessels are half-empty and contain viscous red blood. Pirogov describes this as a symptom of “raspberry jelly.” Dystrophic changes in the myocardium, liver and kidneys.

Upon autopsy, a large amount of liquid contents is found in the intestines. Microscopy of the intestinal wall reveals signs of exudative inflammation, but desquamation of the epithelium and ulcers are not found. This makes it possible to distinguish cholera enteritis from salmonella and other enteritis.

The incubation period lasts 1-5 days. Quarantine is imposed for this period (5 days). Periods of the disease:

Cholera enteritis

Gastroenteritis (vomiting)

Algid period - a violation of microcirculation leads to the fact that the skin becomes cold.

Options for the development of the disease:

Recovery occurs when the body’s protective function is sufficiently pronounced.

When a large number of microbes enter the body and the protective function is not sufficiently expressed, the asphyxial form of cholera develops, that is breathing disorder, disturbance of central nervous activity (coma) and ultimately death.

Classification by Academician Pokrovsky (according to the degree of dehydration):

1 - the patient’s body weight deficiency is 1-3%

2 - deficit 4-6%

3 - deficit 7-9%

4 - 10% or more. The fourth degree is hypovolemic dehydration shock.

Typical and atypical forms diseases. Typical forms are when there is enteritis, followed by gastritis, and there is dehydration.

An atypical form, when the changes are minor, erased, dehydration practically does not develop. Also considered atypical are such pronounced forms as fulminant, dry cholera (severe dehydration, but without frequent diarrhea, there is severe hypokalemia, intestinal paresis, fluid in the pleural cavity).

The onset of the disease is acute. The first symptom is loose stools. Urges are imperative. Features of diarrhea syndrome:

The temperature does not increase (the maximum increase in temperature on the first day is 37.2 -37.5)

There is no pain syndrome.

The first portions of feces are semi-formed in nature, and subsequently they lose their fecal character, there are no impurities, feces resemble the appearance of rice water (whitish, sometimes with a yellowish tint, with flakes, watery stools). Subsequently, vomiting occurs. The first period is the period of enteritis. After a few hours, sometimes after 12 hours - 24 hours, vomiting occurs (a manifestation of gastritis). As a result of manifestations of gastroenteritis, dehydration and demineralization quickly occur. Loss of fluid leads to hypovolemia, and loss of salts leads to seizures. Most often these are the muscles of the hands, feet, chewing muscles, and lower leg muscles.

With an unfavorable course of the disease, stool frequency increases, blood pressure decreases, sharp tachycardia is observed, widespread cyanosis appears, skin turgor and elasticity decrease, and the “washerwoman’s hand” symptom is noted. Hypovolemia leads to decreased diuresis. Oligouria develops, and subsequently anuria.

With the development of hypovolemic shock (grade 4 dehydration), diffuse cyanosis is observed. The facial features become sharper, the eyeballs sink deeply, and the face itself expresses suffering. This is called facies cholerica. The voice is initially weak, quiet, and then disappears (aphonia) with 3-4 degrees of dehydration.

Body temperature at the height of the disease drops to 35-34 degrees.

In severe cases of the disease, heart sounds cannot be heard, blood pressure cannot be determined, and shortness of breath increases to 60 breaths per minute. Accessory muscles are involved in the act of breathing. Difficulty in breathing is also caused by muscle spasms, including the diaphragm. Convulsive contraction of the diaphragm explains the hiccups in these patients.

Terminal period: consciousness is quickly lost and patients die in a coma.

Hematogram

Specific gravity of blood	2nd degree	3rd degree	4th degree
Hematocrit,%

Diagnosis of the disease.

A complex of subjective data is taken into account, including epidemiological history, the dynamics of the disease, the change from enteritis to gastroenteritis, and rapid dehydration.

Objective examination: decreased turgor, skin elasticity, blood pressure control, diuresis control.

LABORATORY DIAGNOSTICS:

main indicators: specific gravity of blood plasma, control of hematocrit, electrolytes

specific diagnostics:

microscopy of feces - a characteristic type of pathogens (located in parallel in the form of schools of fish, mobile). This allows a preliminary diagnosis to be made.

A classic study at the first stage involves inoculating with 1% alkaline peptone water, followed by removing the film and performing a detailed agglutination reaction with anticholera 0-1 serum. When a positive reaction is obtained with O-1 serum, a standard agglutination reaction is performed with Inaba and Agave serums. This allows you to determine the serotype.

Determination of vibrio biotype (classic or El Tor). The phages used are (type) phage El-Tor 2 and phage Inkerdzhi 4. Classic biotype, when lysability to Inkerdzhi phages is exposed. El Tor, when vibrios are lysed by El Tor2 phages.

ACCELERATED DIAGNOSTIC METHODS.

1. Method of macroagglutination of vibrios after growing on peptone water (response after 4 hours)

2. Microagglutination method for vibrio immobilization. When serum is added, vibrios lose their mobility (immobilize). Reply in a few minutes.

3. Method of fluorescent antibodies (in the presence of a fluorescent microscope). Reply in 2 hours.

Serological methods - detection of vibrocidal and antitoxic antibodies. These methods are of lesser importance.

DIFFERENTIAL DIAGNOSTICS.

It is carried out with salmonellosis, food toxic infections, escherichiosis, campylobacteriosis.

Hospitalization is required. Cases require reporting to WHO.

At the first stage - pathogenetic therapy: replenishment of fluid loss - rehydration, performed in two stages:

Primary rehydration - depending on the degree of dehydration (for a person 70 kg, degree 4 dehydration (10%) - 7 liters are transfused)

Correction of ongoing losses (those that already occur in the clinic).

Primary rehydration is carried out by intravenous administration of fluid into 2-3 veins. Use Philips solution 1 or Trisol solution. It is necessary to heat these solutions to a temperature of 37 degrees. Even if pyrogenic reactions occur in response to the administration of solutions, further administration is necessary under the guise of pipolfen, diphenhydramine and hormones.

After primary rehydration, when health improves, blood pressure rises, diuresis switches to Phillips solution 2 or disol solution (sodium chloride to bicarbonate 6 to 4, no potassium chloride), since hyperkalemia develops during primary rehydration).

During the first hours in the clinic, fluid is administered intravenously (at a rate of 1-2 liters per hour). Subsequently, the frequency of drops becomes normal - 60-120 per minute.

Mild disease - oral rehydration (rehydrol, glucosoran) is used. Specific drugs - tetracyclines. Tetracyclines are prescribed 300 mg 4 times a day. The course of treatment is 5 days.

Levomycetin - 500 mg 4 times a day. If there is no effect from these drugs, you can get a good effect from doxycycline (semi-synthetic tetracycline). On the first day, 1 tablet. 2 times a day. For days 2-3-4, 1 tablet. 1 time per day. Tablets 0.1.

There are studies that indicate a good effect of furadonin at a dosage of 0.1 4 times a day. It is necessary to include foods rich in potassium in your diet (dried apricots, etc.).

Antibacterial therapy is prescribed orally. If the patient has severe gastroenteritis and vomiting, then oral therapy will be ineffective. Levomycetin succinate 1 g is prescribed 3 times a day intramuscularly.

Patients are discharged after their recovery and a threefold negative bacteriological examination of stool. The study is done 7 days after treatment with antibiotics three times with an interval of 24 hours (inoculation in 1% alkaline media). If this is a decreed contingent (medics, working with children, catering workers), then it is necessary to obtain a negative bile culture.

TYPES OF HOSPITALS DEPLOYED DURING A CHOLERA OUTBREAK

Cholera hospital - patients with a confirmed bacteriological diagnosis of cholera.

Provisional hospital - for patients with diarrhea syndrome; bacteriological research has not yet been carried out. Conduct a bacteriological study. If there is cholera vibrio, they are transferred to a cholera hospital; if it is salmonellosis, they are transferred to a regular infectious diseases department.

Observation hospital - all contact persons are hospitalized for 45 days. Bacteriological research and observation are carried out.

MEDICAL TACTICS IN DETECTING A CHOLERA PATIENT.

It is prohibited to enter or leave the room where the patient is located.

Urgently inform the head physician of the institution of the preliminary diagnosis of cholera.

It is prohibited to throw feces and vomit into the sewer.

Write down the contact persons (in pencil on a piece of paper so that it does not discolor during disinfection).

Provide emergency care to the patient (recovery from shock).

Collection of stool and vomit for bacteriological examination.

An epidemiologist, a consultant on special needs should come to the patient dangerous infections and representative medical institution, who will coordinate actions.

Subsequently, the doctor who identified the patient is admitted to the hospital as a contact. Urgent chemoprophylaxis is necessary (even before the arrival of consultants or an epidemiologist).

PREVENTION

There is a vaccine and a cholerogen toxoid to produce antibodies to the choleragen.

Residents of developed countries have long forgotten what cholera is, where the standard of living is quite high, prevention of cholera in the event of an epidemic risk is carried out quickly, and the quality of medical care is at the proper level.

However, not everything is so rosy on a global scale. Europe is not afraid of an outbreak of the disease within itself, but it is afraid (and not unreasonably) of its movement from exotic countries. That is why it is important to know the causes of cholera, its main manifestations and rules of behavior in such a situation.

Plague, cholera and anthrax are considered long-forgotten diseases that caused terrible epidemics. Their victims numbered in the tens of thousands. If plague and anthrax have recently been extremely rare, in isolated cases, then from cholera every year from 3 to 5 million people suffer and up to 150 thousand die.

Cholera is a dangerous infectious disease that affects the mucous membranes of the small intestine. The causative agent of cholera is Vibrio cholerae, Vibrio cholerae.

The pathogenesis of cholera is determined by the structure of the pathogenic microorganism, which has the following features:

The presence of a flagellum that ensures the motility of the bacterium;
purposefulness in movement towards nutrients;
releases exotoxin, a cholerogen that activates chemical reactions in the intestines. Leads to diarrhea with extreme dehydration;
enzymes released during vital activity destroy the integrity of the mucous layer and allow bacteria to enter the muscular layer of the intestine;
The cholera vibrio has pili - a kind of suckers that help it to gain a foothold on the intestinal walls, multiply and colonize.

The causative agent of cholera, entering the human body, overcomes the gastric barrier and enters the small intestine. It is here that it is activated, releasing toxins that trigger the development of cholera symptoms.

It should be noted that the causative agent of the disease does not form spores or capsules. But despite the absence protective functions, quite stable in the external environment. It can remain active in ice and river water for up to a month, and in sea water. In the feces of a sick person - up to 3 days, in soil - up to 3 months.

However high temperatures(when boiling or processing vegetables and fruits with boiling water they die instantly), drying, exposure sun rays, treatment with antiseptics and disinfectant solutions leads to the death of the vibrio.

Routes of infection

Cholera like infectious disease, threatens all inhabitants of the earth. Until 1817, it “lived” only in India, but then it spread beyond its borders. Now it is recorded in 90 countries around the world.

The unsanitary conditions in which people live in the countries of Latin America, Africa, and Southeast Asia provoke outbreaks of the disease every year.

There is a risk of contracting the disease among tourists who prefer to holiday in the Dominican Republic, Cuba, Haiti and Martinique.

Social cataclysms, earthquakes and other natural disasters that leave people without quality drinking water become the cause of the disease. The last cholera epidemic was registered in 2010, when there were more than 200 thousand cases.

The source of infection is a sick person or a carrier. The transmission mechanism is exclusively fecal-oral. There are no bowel movements during this period specific smell and colors, so they can go unnoticed. The disease is not transmitted by airborne droplets.

Transmission routes:

Through contaminated water into which wastewater enters. In such water the concentration of the pathogen is very high, it is dangerous to wash with it, use it for cooking or drink;
household contact infection occurs through objects;
food - through seafood, algae, dairy products, fruits and vegetables, fish and meat that have not been subjected to heat treatment. Bacteria on these products can come from either the source or be carried by flies.

Risk factors for developing cholera infection include:

Use of water from reservoirs contaminated by sewage. This “liquid” cannot be used for hygiene or household needs;
seafood that has not been sufficiently cooked (especially raw shellfish and seaweed);
travel to “third world” countries where the standard of living is low and SanPiN rules are not observed;
refugee camps where there is no elementary conditions for life (sewage, drinking water);
military operations and epicenters of natural or social disasters.

People with organ diseases are also at risk digestive system(low acidity of gastric juice or disturbances in the functioning of the organ that produces hydrochloric acid).

Clinical picture

Symptoms of cholera are usually moderate with an average pathology development. The incubation period can last either several hours (with the fulminant form) or 3-5 days. During this time, the vibrio colonizes the intestines and begins its life activity.

The signs of cholera are as follows:

Starts suddenly in the morning or night frequent urges to bowel movement;
temperature indicators remain within normal limits or do not increase significantly;
then gushing vomiting without painful sensations or nausea;
there is rumbling and discomfort in the lower abdomen and in the navel area;
the stool is frequent, at first just liquid, then it takes on the consistency and appearance of rice water, without any particular odor or with a slight fish or potato aroma;
loss of appetite, muscle weakness and constant strong thirst;
increased heart rate due to decreased blood pressure;
dry skin and mucous membranes in the mouth. In some cases, the skin may take on a bluish tint.

With further development without adequate treatment stool becomes even more frequent, due to dehydration, cramps appear in the muscles of the legs and arms, the amount of urine excreted decreases down to complete absence. The voice becomes hoarse. Loose stools are observed from several hours to 1-2 days - with timely seeking help and adequate therapy.

The cholera clinic will differ depending on the severity of the pathology.

A mild degree is the most favorable scenario for the course of the disease, ending with complete recovery without consequences for the body. The symptoms are as follows:

General weakness, thirst and dry mouth;
diarrhea up to 10 times a day;
may occur without vomiting or with rare manifestations;
fluid loss up to 3% of body weight in adults and up to 2% in children.

All these symptoms disappear within two to three days.

There is a version that with frequent and regular fluid intake during this period, cure is possible even without taking medications.

Moderate severity is characterized by the following clinical manifestations:

The onset is rapid, loose stools up to 20 times a day;
gushing frequent vomiting without nausea or discomfort;
the organ (intestines) is not painful;
general weakness, constant thirst, provoked by the second degree of dehydration, cramps of the calf muscles.

The severe form is characterized by a stool frequency of more than 20 times per bowel movement, uncontrollable vomiting, and the third degree of dehydration (fluid loss of more than 10% of the total body weight, critical for the human body).

All other symptoms are very pronounced and increase over time. If assistance is not provided in a timely manner, in 60% of cases the disease ends in death.

Cholera in children is most often observed between the ages of 3 and 5 years and is severe. Older children, especially those who have been vaccinated, get sick less often and in mild form. In newborns, most cases are fatal.

Note: Children whose mothers have had cholera have strong immunity to the disease and even infancy if they get sick, it is in a mild form with complete recovery without any complications.

The algic form of cholera (or rather, the period of pathology) is the most difficult period, during which mortality is noted.

Diagnosis and treatment

If there is no epidemic or at its very beginning, when isolated cases of intestinal infections are identified, the diagnosis is made in stages.

An anamnesis is collected based on the patient's complaints and symptoms. The circle of his contacts over the past few days is revealed. This makes it possible to observe people who are sick, either carriers or potential patients.

Next, laboratory diagnostics of cholera is carried out - examination of vomit and feces. The material is collected immediately before the analysis. If within 3 hours it was not possible to carry out necessary research, then the material is placed in alkaline environment. It is often possible to identify the pathogen within 36 hours, and in specialized laboratories – within 5 hours, which is very important for treatment.

As an auxiliary method, a serological test is used to detect antibodies in the blood.

Treatment for cholera includes:

Relieve symptoms through rehydration. With mild and medium degree severity - orally, for moderate and severe - intravenously;
restoration of water-mineral balance through intravenous administration of appropriate drugs;
prescribing choleretic drugs - narrow-spectrum antibiotics (acting specifically on Vibrio cholerae), but sometimes antibacterial drugs are prescribed wide range actions. Therapy is carried out for at least 5 days.

When improvement begins and a person can eat, experts do not recommend sticking to any special diets. Dishes should not be too fatty, spicy or salty. Meals are fractional and frequent, but in small portions. There are no special restrictions on products.

Preventive actions

Cholera prevention is carried out in countries where there is a risk of an epidemic outbreak or cases of the disease have been reported. Such measures can be divided into planned and emergency.

Directly at the place where the disease is detected, it is prohibited to swim in open waters, drink raw water. Water is disinfected with special reagents.
Patients are strictly isolated until complete recovery.
People who had contact with the patient are being monitored. They are also examined for infection within five days.
It is mandatory to wash your hands with soap and other antiseptics, handle dishes and food hot water and, if possible, disinfectants.

In European countries, for preventive purposes, people returning from countries where cases of cholera were reported during their stay are monitored for 5 days.

Vaccination against cholera is a specific preventive measure. Modern research has proven that injectable vaccines should only be used in an emergency. According to epidemiological indicators, no earlier than 3 months later, revaccination can be carried out, providing one hundred percent protection against the disease.

But the use of oral vaccines, of which there are three types, is more justified. They are recommended for those who plan to visit potentially dangerous regions. But this must be done in advance (about 10-14 days before the planned trip).

The disadvantage of such vaccination is that it protects against the disease for a short time– from several months to six months, no more.

Complications of cholera, especially if treatment was started at the wrong time or was carried out using inadequate methods, may be as follows:

At weak immunity, availability concomitant diseases possible development of abscesses and phlegmons;
sepsis has recently been extremely rare, but in countries with low level life still takes place;
with severe pathology and fourth degree dehydration, dehydration shock may develop - blueing of certain areas of the skin, decreased body temperature, loss of voice, tachycardia and a decrease in blood pressure to critical levels;
disturbances in the functioning of the brain and, as a consequence, coma.

One should not think that cholera is somewhere far away and not with us. As shown last epidemic in 2010, such a misfortune can overtake a person in any country in the world.