What causes plague in people? Plague disease - is there a risk of getting sick these days? Origin of the name smallpox

acute infectious disease caused by bacteria Yersinia pestis and manifests itself in two main forms - bubonic and pulmonary. In nature, plague is common among rodents, from which it is transmitted to humans through the bite of infected fleas. The predominant form of plague in humans, bubonic plague, is characterized by inflammation of the lymph nodes (most often the groin); In appearance, the enlarged lymph nodes resemble beans, which is where the name of the disease comes from: “Jumma” - Arabic. "bean".

Historical aspect.

In the history of mankind, devastating plague epidemics have left in people’s memory the idea of this disease as a terrible disaster, surpassing in damage caused the destructive consequences of malaria or typhus epidemics that “decimated” entire armies for past civilizations. One of the most amazing facts in the history of plague epidemics is their resumption over vast territories after long periods (centuries) of relative prosperity. The three worst plague pandemics are separated by periods of 800 and 500 years.

Some experts believe that the first historical references to the plague are contained in the fifth and sixth chapters of the First Book of Kings, which describe an epidemic in which the Philistines were stricken with "growths." These same authors admit that the “growths” mean plague buboes, and the “five golden growths and five golden mice” demanded from the Philistines indicate that already in ancient times they probably guessed about the connection between the plague and rodents. It is generally accepted that the philosopher and physician Sushruta, who lived in India in the 5th century. AD, also knew about the connection between plague epidemics and rodents.

Rufus of Ephesus (1st century AD) described a major epidemic of an infectious disease, accompanied by the development of buboes and high mortality, in the territory of present-day Egypt, Libya and Syria. The first huge pandemic recorded in the annals occurred during the reign of Justinian, in 542. The second major pandemic, known as the Black Death, swept the world in the 14th century, with a maximum incidence in 1347-1350. It claimed about a quarter of the population of Europe and led to changes in the spiritual, social and economic spheres of society. The epidemic of the "Great Plague" in England in 1665 was limited mainly to London. A severe outbreak of plague occurred in Marseilles in 1720. Following these epidemics, local outbreaks were noted in a number of port cities of the world; the plague, however, did not spread deep into the continents. The third major pandemic began in the 19th century. in China and reached Hong Kong in 1894. On ships, along with infected rats, the plague quickly spread from this great port to India, the Near and Middle East, Brazil, California and other regions of the world. Over a 20-year period, about 10 million people died from the pandemic.

Epidemiology.

The main carriers of plague pathogens are rodents, mainly rats, ground squirrels, coyotes, ground squirrels, jerboas - about 300 species in total. Plague is always transmitted to humans from a natural reservoir - from infected animals. In cities, plague bacteria persist among rats and mice; It is rats that serve as the main source of human infection. In rural areas, the main carriers of infection are field or forest rodents living in the area. In some regions of Siberia, Manchuria, South Africa, South America and the United States, the incidence of plague is endemic: cases of infection are limited to certain areas of distribution of animals. In the US, the disease has been reported mainly in the southwestern part of the country: in California, Nevada, Colorado, Arizona and New Mexico.

Cases of the plague are believed to occur in almost every country, with relatively high incidence rates reported in India, Burma, Vietnam, Brazil, Peru, Tanzania, Madagascar and the Philippines. Susceptibility to plague does not vary by race, age, or gender. Bubonic plague is more common in areas with average temperatures below 27°C; at 29°C epidemics begin to wane. The pneumonic form of plague is observed mainly in the cool seasons of the year and occurs mainly in countries with a temperate, humid climate. However, in 1994, an outbreak of pneumonic plague occurred in Surat (India), located in the tropical part of the country.

The incubation period lasts 2–10 days. Bubonic plague is characterized by a sudden onset in the form of severe chills, rapid fever, severe headache, dizziness, thirst, and vomiting. Inflammation develops in the regional lymph nodes closest to the site of the flea bite; they increase in size, forming buboes, and become very painful. Most often the lymph nodes of the groin area are affected, but sometimes also the axillary, cervical and other lymph nodes. As a consequence of severe intoxication, patients quickly develop a state of complete prostration (stupefaction and lethargy), confusion and coma. Some patients, on the contrary, experience agitation, delusions, hallucinations, and a desire to escape. Plague is a short-lived disease: death or a turning point in the disease occurs within a few days. In the septic form of plague, the clinical picture of infectious-toxic shock develops so quickly that patients die from cardiovascular failure and hemorrhagic syndrome even before the development of buboes. Bubonic plague can be complicated by pneumonia, which at one time almost always led to death. In major epidemics of bubonic plague, the mortality rate reached 90%.

The pneumonic form of plague is characterized by the fact that within the first 24 hours after a sudden onset, severe chills and a rapid rise in temperature cause chest pain and bloody, frothy sputum. The course of this form of the disease is very rapid: before the era of antibiotics, patients died within 2–4 days. Currently, if the disease can be recognized early and antibiotics administered within the first 24 hours, recovery occurs in many cases.

Treatment and prevention.

With the introduction of antibiotics, the prognosis of the disease has become more favorable, although absolutely reliable treatments do not exist. It is very important to start treatment as early as possible. Streptomycin is most effective against all forms of plague and has fewer side effects compared to other antibiotics. Those who travel to “plague areas” are recommended to take daily prophylactic tetracycline during the period of possible infection.

Plague is included in the group of especially dangerous infections. Therefore, measures to prevent its spread are of paramount importance. In endemic areas, rat extermination must be carried out. Suspected cases of plague should be reported immediately to local health authorities. Patients with pneumonic plague should be immediately isolated from others, since this form of infection is the most contagious. It is recommended that all those in contact with the patient be subjected to quarantine examination.

They also belong to the Ancient World. Thus, Rufus from Ephesus, who lived during the time of Emperor Trajan, referring to more ancient doctors (whose names have not reached us), described several cases of definitely bubonic plague in Libya, Syria and Egypt.

The Philistines did not calm down and for the third time transported the trophy of war, and with it the plague, to the city of Ascalon. All the Philistine rulers later gathered there - the kings of the five cities of Philistia - and they decided to return the ark to the Israelites, because they realized that this was the only way to prevent the spread of the disease. And chapter 5 ends with a description of the atmosphere that reigned in the doomed city. “And those who did not die were smitten with growths, so that the cry of the city went up to heaven” (1 Sam.). Chapter 6 depicts the council of all the rulers of the Philistines, to which priests and soothsayers were called. They advised to bring a trespass offering to God - to put gifts in the ark before returning it to the Israelites. “According to the number of the rulers of the Philistines, there are five golden growths and five golden mice that devastate the land; for the execution is one for all of you and for those who rule you” (1 Sam.). This biblical legend is interesting in many respects: it contains a hidden message about an epidemic that most likely swept through all five cities of Philistia. We could be talking about the bubonic plague, which affected people young and old and was accompanied by the appearance of painful growths in the groin - buboes. The most remarkable thing is that the Philistine priests apparently associated this disease with the presence of rodents: hence the golden sculptures of mice “ravaging the earth.”

There is another passage in the Bible that is considered to be a record of another instance of the plague. The Fourth Book of Kings (2 Kings) tells the story of the campaign of the Assyrian king Sennacherib, who decided to devastate Jerusalem. A huge army surrounded the city, but did not take control of it. And soon Sennacherib withdrew without a fight with the remnants of the army, in which the “Angel of the Lord” struck 185 thousand soldiers overnight (2 Kings).

Plague epidemics in historical times

Plague as a biological weapon

The use of the plague agent as a biological weapon has deep historical roots. In particular, events in ancient China and medieval Europe showed the use of the corpses of infected animals (horses and cows), human bodies by the Huns, Turks and Mongols to contaminate water sources and water supply systems. There are historical reports of cases of ejection of infected material during the siege of some cities (Siege of Kaffa).

Current state

Every year, the number of people infected with plague is about 2.5 thousand people, with no downward trend.

According to available data, according to the World Health Organization, from 1989 to 2004, about forty thousand cases were recorded in 24 countries, with a mortality rate of about 7% of the number of cases. In a number of countries in Asia (Kazakhstan, China, Mongolia and Vietnam), Africa (Congo, Tanzania and Madagascar), and the Western Hemisphere (USA, Peru), cases of human infection are recorded almost every year.

At the same time, on the territory of Russia, over 20 thousand people are at risk of infection every year in the territory of natural foci (with a total area of more than 253 thousand km²). For Russia, the situation is complicated by the annual identification of new cases in states neighboring Russia (Kazakhstan, Mongolia, China), and the importation of a specific carrier of the plague - fleas - through transport and trade flows from the countries of Southeast Asia. Xenopsylla cheopis .

From 2001 to 2006, 752 strains of the plague pathogen were recorded in Russia. At the moment, the most active natural foci are located in the territories of the Astrakhan region, the Kabardino-Balkarian and Karachay-Cherkess republics, the republics of Altai, Dagestan, Kalmykia, and Tyva. Of particular concern is the lack of systematic monitoring of the activity of outbreaks located in the Ingush and Chechen Republics.

In July 2016, in Russia, a ten-year-old boy with bubonic plague was taken to the hospital in the Kosh-Agach district of the Altai Republic.

In 2001-2003, 7 cases of plague were registered in the Republic of Kazakhstan (with one death), in Mongolia - 23 (3 deaths), in China in 2001-2002, 109 people fell ill (9 deaths). The forecast for the epizootic and epidemic situation in the natural foci of the Republic of Kazakhstan, China and Mongolia adjacent to the Russian Federation remains unfavorable.

At the end of August 2014, an outbreak of plague occurred again in Madagascar, which by the end of November 2014 had claimed 40 lives out of 119 cases.

Forecast

Under modern therapy, mortality in the bubonic form does not exceed 5-10%, but in other forms the recovery rate is quite high if treatment is started early. In some cases, a transient septic form of the disease is possible, which is poorly amenable to intravital diagnosis and treatment (“fulminant form of plague”).

Infection

The causative agent of plague is resistant to low temperatures, preserves well in sputum, but at a temperature of 55 ° C it dies within 10-15 minutes, and when boiled, almost instantly. The gate of infection is damaged skin (with a flea bite, as a rule, Xenopsylla cheopis), mucous membranes of the respiratory tract, digestive tract, conjunctiva.

Based on the main carrier, natural plague foci are divided into ground squirrels, marmots, gerbils, voles and pikas. In addition to wild rodents, the epizootic process sometimes includes so-called synanthropic rodents (in particular, rats and mice), as well as some wild animals (hares, foxes) that are the object of hunting. Among domestic animals, camels suffer from the plague.

In a natural outbreak, infection usually occurs through the bite of a flea that previously fed on a sick rodent. The likelihood of infection increases significantly when synanthropic rodents are included in the epizootic. Infection also occurs during hunting of rodents and their further processing. Massive diseases of people occur when a sick camel is slaughtered, skinned, butchered, or processed. An infected person, in turn, is a potential source of plague, from which the pathogen can be transmitted to another person or animal, depending on the form of the disease, by airborne droplets, contact or transmission.

Fleas are a specific carrier of the plague pathogen. This is due to the peculiarities of the device of the digestive system of fleas: in front of the stomach, the esophagus of the flea forms a thickening - goiter. When bitten by an infected animal (rat), the plague bacterium settles in the flea's crop and begins to multiply intensively, completely clogging it (the so-called "plague block"). Blood cannot enter the stomach, so the flea regurgitates the blood, along with the pathogen, back into the wound. And since such a flea is constantly tormented by a feeling of hunger, it switches from host to host in the hope of getting its portion of blood and manages to infect a large number of people before it dies (such fleas live no more than ten days, but experiments on rodents showed that one flea can infect up to 11 hosts).

When bitten by fleas infected with plague bacteria, a papule or pustule may appear at the site of the bite, filled with hemorrhagic contents (skin form). The process then spreads through the lymphatic vessels without the appearance of lymphangitis. The proliferation of bacteria in macrophages of the lymph nodes leads to their sharp increase, fusion and formation of a conglomerate (“bubo”). Further generalization of the infection, which is not strictly necessary, especially in the conditions of modern antibacterial therapy, can lead to the development of a septic form, accompanied by damage to almost all internal organs. From an epidemiological point of view, it is important that plague bacteremia develops, as a result of which a sick person himself becomes a source of infection through contact or transmission. However, the most important role is played by the “screening out” of infection into the lung tissue with the development of the pulmonary form of the disease. From the moment plague pneumonia develops, the pulmonary form of the disease is already transmitted from person to person - extremely dangerous, with a very rapid course.

Symptoms

The bubonic form of the plague is characterized by the appearance of sharply painful conglomerates, most often inguinal lymph nodes on one side. The incubation period is 2-6 days (less often 1-12 days). Within a few days, the size of the conglomerate increases, the skin over it may become hyperemic. At the same time, there is an increase in other groups of lymph nodes - secondary buboes. The lymph nodes of the primary focus undergo softening, and when they are punctured, purulent or hemorrhagic contents are obtained, the microscopic analysis of which reveals a large number of gram-negative rods with bipolar staining. In the absence of antibiotic therapy, suppurated lymph nodes are opened. Then gradual healing of the fistula occurs. The severity of the patient's condition gradually increases by the 4th-5th day, the temperature may be elevated, sometimes a high fever appears immediately, but at first the condition of the patients often remains generally satisfactory. This explains the fact that a person with bubonic plague can fly from one part of the world to another, considering himself healthy.

However, at any time, the bubonic form of the plague can cause a generalization of the process and go into a secondary septic or secondary pulmonary form. In these cases, the condition of the patients very quickly becomes extremely serious. Symptoms of intoxication increase by the hour. The temperature after severe chills rises to high febrile levels. All signs of sepsis are noted: muscle pain, severe weakness, headache, dizziness, congestion of consciousness, up to its loss, sometimes agitation (the patient rushes about in bed), insomnia. With the development of pneumonia, cyanosis increases, a cough appears with the release of foamy, bloody sputum containing a huge amount of plague bacilli. It is this sputum that becomes the source of infection from person to person with the development of the now primary pneumonic plague.

Septic and pneumonic forms of plague occur, like any severe sepsis, with manifestations of disseminated intravascular coagulation syndrome: minor hemorrhages may appear on the skin, bleeding from the gastrointestinal tract is possible (vomiting of bloody masses, melena), severe tachycardia, rapid and requiring correction ( dopamine) drop in blood pressure. Auscultation reveals a picture of bilateral focal pneumonia.

Clinical picture

The clinical picture of the primary septic or primary pulmonary form is not fundamentally different from the secondary forms, but the primary forms often have a shorter incubation period - up to several hours.

Diagnosis

The most important role in diagnosis in modern conditions is played by epidemiological anamnesis. Arrival from zones endemic for plague (Vietnam, Burma, Bolivia, Ecuador, Karakalpakstan, etc.), or from anti-plague stations of a patient with the signs of the bubonic form described above or with signs of the most severe - with hemorrhages and bloody sputum - pneumonia with severe lymphadenopathy is for doctor of first contact is a sufficiently serious argument for taking all measures to localize the suspected plague and accurately diagnose it. It should be especially emphasized that in the conditions of modern drug prevention, the likelihood of illness among personnel who have been in contact with a coughing plague patient for some time is very small. Currently, there are no cases of primary pneumonic plague (that is, cases of infection from person to person) among medical personnel. An accurate diagnosis must be made using bacteriological studies. The material for them is the punctate of a suppurating lymph node, sputum, the patient’s blood, discharge from fistulas and ulcers.

Laboratory diagnosis is carried out using a fluorescent specific antiserum, which is used to stain smears of discharge from ulcers, punctate lymph nodes, and cultures obtained on blood agar.

Treatment

In the Middle Ages, the plague was practically not treated; actions were reduced mainly to cutting out or cauterizing the plague buboes. No one knew the real cause of the disease, so there was no idea how to treat it. Doctors tried to use the most bizarre means. One such drug included a mixture of 10-year-old molasses, finely chopped snakes, wine and 60 other ingredients. According to another method, the patient had to take turns sleeping on his left side, then on his right. Since the 13th century, attempts have been made to limit the plague epidemic through quarantines.

A turning point in plague treatment was reached in 1947, when Soviet doctors were the first in the world to use streptomycin to treat plague in Manchuria. As a result, all patients who were treated with streptomycin recovered, including a patient with pneumonic plague, who was already considered hopeless.

Treatment of plague patients is currently carried out using antibiotics, sulfonamides and medicinal anti-plague serum. Prevention of possible outbreaks of the disease consists of carrying out special quarantine measures in port cities, deratization of all ships that sail on international flights, creating special anti-plague institutions in steppe areas where rodents are found, identifying plague epizootics among rodents and combating them.

Anti-plague sanitary measures in Russia

If plague is suspected, the sanitary and epidemiological station of the area is immediately notified. The notification is filled out by the doctor who suspects an infection, and its forwarding is ensured by the chief physician of the institution where such a patient was found.

The patient should be immediately hospitalized in the infectious diseases hospital. A doctor or paramedical worker of a medical institution, upon discovering a patient or suspected of having the plague, is obliged to stop further admission of patients and prohibit entry and exit from the medical institution. While remaining in the office or ward, the medical worker must inform the chief physician in a way accessible to him about the identification of the patient and demand anti-plague suits and disinfectants.

In cases of receiving a patient with lung damage, before putting on a full anti-plague suit, the medical worker is obliged to treat the mucous membranes of the eyes, mouth and nose with streptomycin solution. If there is no cough, you can limit yourself to treating your hands with a disinfectant solution. After taking measures to separate the sick person from the healthy, a list of persons who had contact with the patient is compiled in a medical institution or at home, indicating the last name, first name, patronymic, age, place of work, profession, home address.

Until the consultant from the anti-plague institution arrives, the health worker remains in the outbreak. The issue of its isolation is decided in each specific case individually. The consultant takes the material for bacteriological examination, after which specific treatment of the patient with antibiotics can begin.

When identifying a patient on a train, plane, ship, airport, or railway station, the actions of medical workers remain the same, although the organizational measures will be different. It is important to emphasize that isolation of a suspicious patient from others should begin immediately after identification.

The head doctor of the institution, having received a message about the identification of a patient suspected of plague, takes measures to stop communication between the hospital departments and clinic floors, and prohibits leaving the building where the patient was found. At the same time, organizes the transmission of emergency messages to a higher organization and the anti-plague institution. The form of information can be arbitrary with the obligatory presentation of the following data: last name, first name, patronymic, age of the patient, place of residence, profession and place of work, date of detection, time of onset of the disease, objective data, preliminary diagnosis, primary measures taken to localize the outbreak, position and the name of the doctor who diagnosed the patient. Along with the information, the manager requests consultants and the necessary assistance.

However, in some situations, it may be more appropriate to carry out hospitalization (before establishing an accurate diagnosis) in the institution where the patient is at the time of the assumption that he has plague. Therapeutic measures are inseparable from the prevention of infection of personnel, who must immediately put on 3-layer gauze masks, shoe covers, a scarf made of 2 layers of gauze that completely covers the hair, and protective glasses to prevent splashes of sputum from entering the mucous membrane of the eyes. According to the rules established in the Russian Federation, personnel must wear an anti-plague suit or use special means of anti-infective protection with similar properties. All personnel who had contact with the patient remain to provide further assistance to him. A special medical post isolates the compartment where the patient and the personnel treating him are located from contact with other people. The isolated compartment should include a toilet and a treatment room. All personnel immediately receive prophylactic antibiotic treatment, continuing throughout the days they spend in isolation.

Treatment of plague is complex and includes the use of etiotropic, pathogenetic and symptomatic agents. Antibiotics of the streptomycin series are most effective for treating plague: streptomycin, dihydrostreptomycin, pasomycin. In this case, streptomycin is most widely used. For the bubonic form of plague, the patient is administered streptomycin intramuscularly 3-4 times a day (daily dose 3 g), tetracycline antibiotics (vibromycin, morphocycline) intramuscularly at 4 g/day. In case of intoxication, saline solutions and hemodez are administered intravenously. A drop in blood pressure in the bubonic form should in itself be regarded as a sign of generalization of the process, a sign of sepsis; in this case, there is a need for resuscitation measures, administration of dopamine, and installation of a permanent catheter. For pneumonic and septic forms of plague, the dose of streptomycin is increased to 4-5 g/day, and tetracycline - to 6 g. For forms resistant to streptomycin, chloramphenicol succinate can be administered up to 6-8 g intravenously. When the condition improves, the dose of antibiotics is reduced: streptomycin - up to 2 g / day until the temperature normalizes, but for at least 3 days, tetracyclines - up to 2 g / day daily orally, chloramphenicol - up to 3 g / day, for a total of 20-25 g. Biseptol is also used with great success in the treatment of plague.

In case of pulmonary, septic form, development of hemorrhage, they immediately begin to relieve disseminated intravascular coagulation syndrome: plasmapheresis is performed (intermittent plasmapheresis in plastic bags can be carried out in any centrifuge with special or air cooling with a capacity of 0.5 l or more) in the volume removed plasma 1-1.5 liters when replaced with the same amount of fresh frozen plasma. In the presence of hemorrhagic syndrome, daily administration of fresh frozen plasma should not be less than 2 liters. Until the acute manifestations of sepsis are relieved, plasmapheresis is performed daily. The disappearance of signs of hemorrhagic syndrome and stabilization of blood pressure, usually in sepsis, are grounds for stopping plasmapheresis sessions. At the same time, the effect of plasmapheresis in the acute period of the disease is observed almost immediately, signs of intoxication decrease, the need for dopamine to stabilize blood pressure decreases, muscle pain subsides, and shortness of breath decreases.

The team of medical personnel providing treatment to a patient with pneumonic or septic form of plague must include an intensive care specialist.

Notes

Disease Ontology release 2019-05-13 - 2019-05-13 - 2019.
Jared Diamond, Guns, Germs and Steel. The Fates of Human Societies.
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Plague - for doctors, students, patients, medical portal, abstracts, cheat sheets for doctors, disease treatment, diagnosis, prevention
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Papagrigorakis, Manolis J.; Yapijakis, Christos; Synodinos, Philippos N.; Baziotopoulou-Valavani, Effie (2006). “DNA examination of ancient dental pulp incriminates typhoid fever as a probable cause of the Plague of Athens” . International Journal of Infectious Diseases. 10 (3): 206-214.

The plague disease, which humanity encountered about one and a half thousand years ago, previously caused large outbreaks of morbidity, claiming tens and hundreds of millions of lives. History does not know anything more merciless and devastating, and so far, despite the development of medicine, it has not been completely possible to cope with it.

What is plague?

Plague is a disease in humans of a naturally focal infectious nature, in many cases resulting in death. This is a highly contagious pathology, and susceptibility to it is universal. After suffering and curing the plague, stable immunity is not formed, that is, the risk of re-infection remains (however, the second time the disease is somewhat milder).

The exact origin of the name of the disease has not been established, but the word “plague” translated from Turkish means “round, bump”, from Greek – “shaft”, from Latin – “blow, wound”. In ancient and modern scientific sources, one can find such a definition as the bubonic plague disease. This is due to the fact that one of the hallmarks of the disease is a bubo - a rounded swelling in the inflamed area. However, there are other forms of infection without the formation of buboes.

Plague is a pathogen

For a long time it was not clear what causes bubonic plague; the pathogen was discovered and associated with the disease only at the end of the 19th century. It turned out to be a gram-negative bacterium from the family of enterobacteria - plague bacillus (Yersinia pestis). The pathogen is well studied, its several subspecies have been identified and the following features have been established:

can have different shapes - from thread-like to spherical;
long-term preservation of viability in the secretions of sick people;
good tolerance to low temperatures and freezing;
high sensitivity to disinfectants, sunlight, acid reaction of the environment, elevated temperatures;
contains about thirty antigenic structures, secretes endo- and exotoxins.

Plague - ways bacteria penetrate the human body

It is important to know how the plague is transmitted from person to person, as well as from other living beings. The plague bacillus circulates in natural infectious foci in the bodies of animal carriers, which include wild rodents (gophers, marmots, voles), gray and black rats, house mice, cats, lagomorphs, and camels. The carriers (distributors) of pathogens are fleas of various types and several types of blood-sucking ticks, which become infected with the pathogen when feeding on sick animals containing the plague bacillus in the blood.

A distinction is made between transmission of the pathogen through fleas from animal carriers to humans and from person to person. We list the possible ways of plague entering the human body:

Transmissible– entry into the bloodstream after the bite of an infected insect.
Contact– when a person who has microtrauma on the skin or mucous membranes comes into contact with the bodies of infected animals (for example, when cutting carcasses, processing hides).
Nutritional– through the mucous membrane of the gastrointestinal tract when eating meat from sick animals that have not undergone sufficient heat treatment, or other contaminated products.
Contact and household– when touched by a sick person, in contact with his biological fluids, using utensils, personal hygiene items, etc.
Aerosol– from person to person through the mucous membranes of the respiratory tract when coughing, sneezing, or close conversation.

Plague - symptoms in humans

The place of introduction of the pathogen determines what form of the disease will develop, with damage to which organs, and with what manifestations. The following main forms of human plague are distinguished:

bubonic;
pulmonary;
septic;
intestinal.

In addition, there are such rare forms of pathology as skin, pharyngeal, meningeal, asymptomatic, and abortive. Plague disease has an incubation period of 3 to 6 days, sometimes 1-2 days (in the case of a primarily pulmonary or septic form) or 7-9 days (in vaccinated or already recovered patients). All forms are characterized by a sudden onset with severe symptoms and intoxication syndrome, manifested in the following:

high body temperature;
chills;
headache;
muscle-joint pain;
nausea;
vomit;
severe weakness.

As the disease progresses, the patient's appearance changes: the face becomes puffy, hyperemic, the whites of the eyes turn red, the lips and tongue become dry, dark circles appear under the eyes, the face expresses fear and horror (“plague mask”). Subsequently, the patient's consciousness is impaired, speech becomes unintelligible, coordination of movements is impaired, delusions and hallucinations appear. In addition, specific lesions develop, depending on the form of the plague.

Bubonic plague - symptoms

Statistics show that bubonic plague is the most common type of disease, which develops in 80% of those infected when the pathogenic bacterium penetrates through the mucous membranes and skin. In this case, the infection spreads through the lymphatic system, causing damage to the inguinal lymph nodes, and in rare cases, the axillary or cervical ones. The resulting buboes can be single or multiple, their size can vary from 3 to 10 cm, and in their development they often go through several stages:

Pneumonic plague

This form is diagnosed in 5-10% of patients, while the plague disease develops after aerogenic infection (primary) or as a complication of the bubonic form (secondary). This is the most dangerous variety, and specific signs of plague in humans in this case are observed approximately 2-3 days after the onset of acute intoxication symptoms. The pathogen infects the walls of the pulmonary alveoli, causing necrotic phenomena. Distinctive manifestations are:

rapid breathing, shortness of breath;
cough;
secretion of sputum - initially foamy, transparent, then streaked with blood;
chest pain;
tachycardia;
drop in blood pressure.

Septicemic form of plague

The primary septic form of plague, which develops when a massive dose of microbes enters the bloodstream, is rare, but it is very difficult. Intoxication symptoms occur at lightning speed, as the pathogen spreads to all organs. There are numerous hemorrhages in the skin and mucous tissues, conjunctiva, intestinal and renal bleeding, rapid development. Sometimes this form proceeds as a secondary complication of other varieties of plague, which is manifested by the formation of secondary buboes.

Intestinal form of plague

Not all experts distinguish the intestinal variety of plague separately, considering it as one of the manifestations of the septic form. When intestinal plague develops, the following signs of illness in people against the background of general intoxication and fever are recorded:

sharp pain in the abdomen;
repeated bloody vomiting;
diarrhea with mucous-bloody stools;
Tenesmus is a painful urge to have a bowel movement.

Plague - diagnosis

Laboratory diagnostics, carried out using the following methods, play a significant role in diagnosing “plague”:

serological;
bacteriological;
microscopic.

For research, they take blood, punctures from buboes, discharge from ulcers, sputum, oropharyngeal discharge, and vomit. To check for the presence of the pathogen, the selected material can be grown on special nutrient media. In addition, X-rays of the lymph nodes and lungs are taken. It is important to establish the fact of an insect bite, contact with sick animals or people, and visiting areas where plague is endemic.

Plague - treatment

If a pathology is suspected or diagnosed, the patient is urgently hospitalized in an infectious diseases hospital in an isolated box, from which direct air outflow is excluded. Treatment of plague in humans is based on the following measures:

taking antibiotics, depending on the form of the disease (Tetracycline, Streptomycin);
detoxification therapy (Albumin, Reopoliglyukin, Hemodez);
the use of drugs to improve microcirculation and repair (Trental, Picamilon);
antipyretic and symptomatic therapy;
maintenance therapy (vitamins, heart medications);
– with septic lesions.

During the period of fever, the patient must remain in bed. Antibiotic therapy is carried out for 7-14 days, after which control studies of biomaterials are prescribed. The patient is discharged after complete recovery, as evidenced by receiving a three-fold negative result. The success of treatment largely depends on the timely detection of plague.

Measures to prevent plague from entering the human body

To prevent the spread of infection, nonspecific preventive measures are taken, including:

analysis of information on the incidence of plague in different countries;
identification, isolation and treatment of people with suspected pathology;
disinfection of transport arriving from plague-prone regions.

In addition, work is constantly carried out in natural foci of the disease: counting the number of wild rodents, examining them to identify the plague bacterium, exterminating infected individuals, and fighting fleas. If even one patient is detected in a locality, the following anti-epidemic measures are carried out:

imposing a quarantine with a ban on the entry and exit of people for several days;
isolation of people who have been in contact with plague patients;
disinfection in areas of disease.

For prophylactic purposes, people who have been in contact with plague patients are given anti-plague serum in combination with antibiotics. Vaccination against plague to a person with a live plague vaccine is given in the following cases:

when you are in natural foci of infection or are about to travel to a disadvantaged area;
during work involving possible contact with sources of infection;
when a widespread infection is detected among animals in the vicinity of populated areas.

Plague - incidence statistics

Thanks to the development of medicine and the maintenance of interstate preventive measures, the plague rarely occurs on a large scale. In ancient times, when no cure for this infection was invented, the mortality rate was almost one hundred percent. Now these figures do not exceed 5-10%. At the same time, how many people have died from the plague in the world recently cannot but be alarming.

Plague in human history

The plague has left devastating traces in human history. The following epidemics are considered the largest:

“The Plague of Justinian” (551-580), which began in Egypt and killed more than 100 million people;
the Black Death epidemic (XIV century) in Europe, brought from Eastern China, which claimed about 40 million lives;
plague in Russia (1654-1655) - about 700 thousand deaths;
plague in Marseille (1720-1722) - 100 thousand people died;
plague pandemic (end of the 19th century) in Asia - more than 5 million people died.

Plague today

Bubonic plague is now found on every continent except Australia and Antarctica. Between 2010 and 2015, more than 3 thousand cases of the disease were diagnosed, with death observed in 584 infected people. Most cases were registered in Madagascar (more than 2 thousand). Foci of the plague have been recorded in countries such as Bolivia, the USA, Peru, Kyrgyzstan, Kazakhstan, Russia and others. Regions of Russia endemic for plague are: Altai, East Ural region, Stavropol region, Transbaikalia, Caspian lowland.

A ten-year-old boy with bubonic plague was taken to the hospital in the Kosh-Agach district of the Altai Republic, reports lenta.ru.

The child was admitted to the infectious diseases department of the district hospital on July 12 with a temperature of about 40 degrees. He is currently in a state of moderate severity. “Specialists found out that he was in contact with 17 people, of which six were children. All of them have been placed in isolation and are under observation. So far, no signs of infection have been detected in them,” the hospital noted.

Health workers suggested that the boy could have contracted the plague while camping in the mountains. It is noted that in the region the disease was recorded in marmots.

Bubonic plague is an infectious disease that has claimed more human lives throughout history than all other diseases combined. Despite all the advances in medicine, it is impossible to completely get rid of the plague, since the causative agent of the disease - the bacterium Yersinia pestis - lives in natural reservoirs, where it infects its main carriers - marmots, gophers and other rodents. These reservoirs exist all over the world and destroying them all is unrealistic.

OpenClipart-Vectors, 2013

Therefore, about three thousand cases of bubonic plague are registered annually in the world, and outbreaks occur even in highly developed countries. Thus, in October 2015, it was reported that a teenage girl from Oregon in the USA was infected with bubonic plague.

However, in countries with an underdeveloped healthcare system, plague outbreaks occur much more often and lead to greater casualties. Thus, in 2014, an outbreak of bubonic plague was registered in Madagascar, which killed 40 people.

In August 2013, doctors confirmed a case of bubonic plague in Kyrgyzstan: 15-year-old Temirbek Isakunov contracted the dangerous disease after eating marmot kebab with his friends.

The marmot is a carrier of plague. PublicDomainPictures, 2010

She commented on this incident on her blog:

The media begins to noisily discuss the possible consequences of the cases of bubonic plague that have appeared in Kyrgyzstan, or more precisely, in how many days will it begin in our country from the Kyrgyz who came to us and cough on us. In this regard, let me remind you that:

1. The danger of the appearance of plague on the territory of Russia is constant, since the plague is a zoonosis, that is, a disease the main reservoir of which is animals. These are gophers and a number of other species living in deserts, semi-deserts, steppes, etc. There are more than a thousand permanent plague foci on the territory of Russia, and there are also a lot of foci in the republics of the former USSR and other neighbors of Russia.

2. The main methods for controlling plague are as follows:

A) Limiting the number of natural hosts (poisoning gophers),

B) Vaccination of those who have to work in these outbreaks,

C) Border control of those who enter (humans and animals)

3. Diseases of people with plague for countries with foci are inevitable. In Russia, the plague causes about one death per year; in the USA, as far as I remember, about 10 die per year.

4. Plague is a particularly dangerous disease due to its high mortality rate. If it is detected, emergency anti-epidemic measures are taken. The plague has a very bad reputation, since in medieval Europe one third of the population died from its epidemics. However, among infectious diseases it now accounts for only a small proportion of deaths. Malaria accounts for the largest number of deaths (more than a million per year).

5. Methods of combating the plague epidemic are very simple. They identify the sick person, drag him into quarantine and treat him, at the same time they grab and drag into quarantine everyone with whom he has been in contact for the last few days. If one of those people gets sick, they seize and isolate those with whom he was in contact. So, in the conditions of a state that is organized enough to carry out such a thing, outbreaks are nipped in the bud.

6. An interesting feature of the plague is that there is one pathogen, but two diseases: pneumonic plague and bubonic plague. The form of development of the disease depends on where the pathogen enters: into the blood or into the lungs.

7. If the pathogen enters the lungs, pneumonic plague develops. It progresses as a rapidly developing acute respiratory infection, followed by hemoptysis and death. From the moment of infection to the first pronounced symptoms - about a day, until death - about 3. Mortality - 100%. It can be successfully treated with some modern antibiotics, but only if treatment is not started too late. Therefore, in the case of pneumonic plague, the outcome depends on the timeliness of hospitalization and the start of treatment, and literally minutes count.

The causative agent of plague is Yersinia pestis. Larry Stauffer, 2002

8. If the pathogen enters the bloodstream, bubonic plague develops - a severe blood fever with a mortality rate (in the absence of antibiotic treatment) of about 50%. The duration of the disease from infection to recovery or death is about a couple of weeks. It got its name from the characteristic giant enlargement of the axillary lymph nodes to formations similar in size and shape to a bunch of grapes.

9. The two indicated forms of plague with the same pathogen are associated with a transmission option. With pneumonic plague, the patient sneezes and coughs, droplets of saliva containing the pathogen scatter and infect others, getting into the lungs. In bubonic plague, the carrier is blood-sucking insects: fleas, lice, etc. People are often infected through bloodsuckers from mice and rats suffering from the plague. By the way, plague epidemics in medieval Europe were also associated with the fact that there were a lot of brown rats. In recent years they have been replaced by another species, white and larger, which is less susceptible to plague.

In principle, it is possible for the plague to transition during epidemics from the bubonic to the pneumonic form and back, but due to these features, epidemics usually occur either only as bubonic, or only as pneumonic.

There is a third, more exotic form of plague - intestinal, when the pathogen enters the stomach, but for this you have to go to India, to the sacred waters of the Ganges...

10. If a plague patient is identified (including a deceased person), due to the above, fun begins, accompanied by panic: platoons of police with machine guns that surround the building with identified contacts, and serious people in anti-plague suits with flamethrowers, scared to death of them (joke).. Over the past 50 years, there have been several (about three) cases of detection of plague being brought into Moscow and several false panics.

11. There is no need to be more scared than usual by people who cough and sneeze. Spraying nearby eastern people with insect repellents from spray cans is the same.

It could be worse

In addition to the plague, outbreaks of an even more dangerous disease - anthrax - are regularly recorded in the vastness of our homeland. The source of this infection is domestic animals: cattle, sheep, goats, pigs. Infection can occur when caring for sick animals, slaughtering livestock, processing meat, as well as through contact with animal products (hides, skins, fur products, wool, bristles) contaminated with spores of the anthrax microbe.

Infection can also occur through soil in which spores of the anthrax pathogen persist for many years. Spores enter the skin through microtraumas; When contaminated foods are consumed, an intestinal form occurs. The high lethality of the pulmonary and intestinal forms, as well as the ability of the pathogen spores to remain viable for many years, are the reason for the use of the anthrax bacillus as a biological weapon.

William Rafti, 2003

The largest epidemic of this disease occurred in 1979 in Sverdlovsk. Since then, small outbreaks of this disease have occurred regularly. Thus, in August 2012, an outbreak of anthrax with fatal cases was recorded in the Altai Territory - in the village of Marushka and the village of Druzhba.

In August 2010, an anthrax outbreak was recorded in the Tyukalinsky district of the Omsk region. The epidemic began with the death of horses on a private farm, which the owners did not report. The dead animals were not even properly buried. As a result, at least six people fell ill, at least one of whom, 49-year-old Alexander Lopatin, died.

In addition, rumors of smallpox cases regularly arise, although the World Health Organization has officially declared the disease eradicated. However, rumors, as a rule, are not confirmed, and one of the last outbreaks of smallpox was recorded in Moscow in the fifties of the last century. He talks about her:

I got vaccinated today at clinic 13 (it was moved from Neglinnaya to Trubnaya St., 19с1, by the way, a long time ago). While they were waiting for the sister, the doctor, an elderly but cheerful, clear-eyed aunt, told a story about the smallpox epidemic in Moscow in the 50s.

I found it on Wiki and am posting it here:

In the winter of 1959 we found ourselves in a bad situation. Moscow artist Kokorekin visited India. He happened to be present at the burning of a deceased Brahmin. Having gained impressions and gifts for his mistress and wife, he returned to Moscow a day earlier than his wife was waiting for him. He spent this day with his mistress, to whom he gave gifts and in whose arms he spent the night, not without pleasure. Having timed the plane's arrival from Delhi, he arrived home the next day. After giving the gifts to his wife, he felt bad, his temperature rose, his wife called an ambulance and he was taken to the infectious diseases department of the Botkin Hospital.

A girl infected with smallpox (Bangladesh). James Hicks, 1975

The senior surgeon on duty, Alexey Akimovich Vasiliev, in whose team I was on duty that day, was called for a consultation in the infectious diseases department with Kokorekin, regarding the imposition of a tracheostomy on him due to breathing problems. Vasilyev, having examined the patient, decided that there was no need to apply a tracheostomy and went to the emergency room. By morning the patient became ill and died.

The pathologist who performed the autopsy invited the head of the department, Academician Nikolai Aleksandrovich Kraevsky, into the dissecting room. An old pathologist from Leningrad came to visit Nikolai Alexandrovich and was invited to the dissecting table. The old man looked at the corpse and said, “Yes, my friend, variola vera is black smallpox.” The old man was right.

Reported to Shabanov. The machine of Soviet health care began to spin. They imposed a quarantine on the infectious diseases department, and the KGB began tracing Kokorekin’s contacts. The story of his early arrival in Moscow and a night of bliss with his mistress was revealed. As it turned out, the wife and mistress behaved in the same way - both ran to thrift stores to hand over gifts. There were several cases of smallpox in Moscow that ended in death. The hospital was quarantined, and it was decided to vaccinate the entire population of Moscow with smallpox vaccine.

There was no vaccine in Moscow, but there was one in the Far East. The weather was bad and no planes were flying. Finally the vaccine arrived and vaccinations began. I suffered it very hard, I did not have immunity against smallpox, although I was vaccinated in 1952, when an epidemic of smallpox began in Tajikistan, brought from Afghanistan in the traditional way - carpets were thrown across the border on which patients with smallpox lay.

Update: I found the details here. It turns out that the ill-fated Kokorekin was present not only at the burning of the Brahmin, who definitely died of smallpox, but also the Brahmin's hut. And I thought - how did he manage to get infected, how? After all, before burning, the body is wrapped in several layers of cloth, and the high temperature of the fire should have killed all the vibrios. But the vibrio is “resistant to the effects of the external environment, especially to drying and low temperatures. It can persist for a long time, for a number of months, in crusts and scales taken from pockmarks on the skin of patients ”(wiki). In that hut there were millions of flakes of skin and dust with vibrios - that’s how I became infected.

And it was after this incident and thanks to the USSR that a program was adopted to eradicate smallpox throughout the world. In the wild forests of India, tribes were shown photographs of people suffering from smallpox. So they rooted it out!

It has natural foci (endemicity), with characteristic lesions of the lymph nodes, skin, lungs and severe general intoxication.

Relevance

Foci of plague are present on all continents except Australia and Antarctica. In the period from 1986 to 2004, the World Health Organization recorded about 24 thousand cases of plague, with a mortality rate of 7% of all cases (this is in the presence of modern antibiotics). The relevance of the infection is also high due to the use of the disease as a biological weapon (along with anthrax).

Historical reference

The first information about the plague dates back to Ancient writings as early as 1200 BC. The symptoms of this infection are also described in the Bible - Old Testament. Throughout the history of mankind, there have been several pandemics (unlike an epidemic, a pandemic is characterized by the involvement of all continents in the infection):

“Justinian Plague” - 500 BC, the beginning of the pandemic occurred in Ancient Egypt, about 100 million people died.
“Black Death” - in the 14th century, brought from China, about 25 million people died.
the third plague pandemic - at the end of the 19th century, the countries of Asia were most affected, but outbreaks of plague were also recorded in Europe.
The plague epidemic in the Far East is currently the last recorded epidemic; about 100 thousand people died.

The bacterium that causes the plague was discovered in 1894 by the French scientist Alexandre Yersin (his name is the specific name of the pathogen - Yersinia).

Etiology of the disease

The causative agent of plague is a rod-shaped bacterium – Yersinia pestis. This is a non-motile bacterium of small size. Yersinia forms a capsule, which makes the microorganism pathogenic and allows it to attach to human cells. At the same time, cells of the immune system (macrophages) cannot actively destroy the pathogen due to the capsule. Another factor is the release of exotoxin and enzymes by the bacterium that facilitate penetration (invasion) into the human body.

In the external environment, the plague causative agent is quite persistent - it can survive in soil for up to several months, however, ordinary disinfectants kill the bacterium within a few minutes.

Epidemiology of the disease

Plague is a zoonotic infection, the main source in natural foci is rodents (ground squirrels, mice, hamsters, rats, hares), in general, about 250 species of animals can accumulate and transmit the pathogen. A considerable number of epidemics are associated with the migration of these animals and the spread of infection. In rodents, plague occurs in a chronic form, so the animal releases the pathogen into the external environment for a long time. Microorganisms are transmitted with the help of fleas, in which the bacteria enter with the blood. In urban areas, the main reservoir of plague are black and gray rats.

transmissible way - infection occurs through the bite of fleas infected from animals;
contact route - when processing carcasses of animals suffering from plague (most often implemented by hunters), this route of plague transmission is also possible if personal safety rules are not followed when caring for a plague-sick person;
nutritional route - when eating meat of infected animals (in Turkmenistan, cases of the disease are known in people who ate gopher meat);
airborne droplets and airborne dust - possible with the pneumonic form of plague in humans, when the pathogen is released in large quantities with exhaled air (the most dangerous route of transmission, since it is possible to infect a large number of people).

The mechanism of the development of the plague

The characteristic development of the plague disease is associated with such a feature of the pathogen as the formation of capsules. When the bacterium enters the skin through a flea bite or through contact, it spreads through the lymphatic vessels and enters the regional lymph nodes. Here the immune defense mechanism turns on, and macrophages try to capture the pathogen. However, thanks to the capsule, incomplete phagocytosis occurs - the bacteria in the macrophages do not die, but begin to multiply. This leads to the development of inflammation and necrosis (death) of the lymph nodes with the formation of buboes (bubonic plague). Next, from the lymphatic vessels, the plague bacterium enters the blood and spreads throughout the body (septic form of plague) with the development of intoxication and multiple organ failure. In this case, the development of infectious-toxic shock and death of the patient is possible. In the pneumonic form of plague, the process is localized in the lungs, the immune system also cannot “cope” with the bacterium, and severe pneumonia occurs.

Plague symptoms

The incubation period (the time from the moment of infection to the appearance of the first signs of the disease) ranges from several hours to 6 days. There are several clinical forms of plague, which depend on the route of transmission:

Specific diagnosis of plague

It consists of using several laboratory diagnostic methods:

microscopic method - is an indicative method, used at the onset of the disease when plague is suspected. To do this, a Gram-stained microscopy of the patient’s material is performed; the result can be obtained in 1-2 hours.
The bacteriological method is the main method for diagnosing plague; the material is inoculated on nutrient media, and after 48 hours the culture is identified. The sensitivity of bacteria to antibiotics is also studied.
serological method - is based on identifying a growing titer of antibodies in the patient’s blood to the plague causative agent; it is important no earlier than a week from the onset of the disease.

Treatment of plague

The effectiveness of treatment depends on how early it is started. Therefore, if plague is suspected, specific etiotropic (aimed at destroying the pathogen in the patient’s body) treatment is started without waiting for laboratory confirmation of the diagnosis. All patients are treated only in a specialized infectious diseases hospital. Patients with the bubonic form of plague are placed in groups of several people in a ward, while those with the pneumonic form are placed only in boxes with one person each. The hospital is under a strict anti-epidemic regime, the staff works in anti-plague suits, all discharge from patients is thoroughly disinfected. Contact people are also isolated and given preventive (preventing the development of the disease) antibiotic therapy.

In general, treatment is divided into the following types:

etiotropic therapy - aimed at destroying the pathogen in the human body, is the main one in treatment; the earlier this therapy is started, the better the prognosis for the patient. Antibiotics are used for this - streptomycin, tetracycline, doxycycline. If these antibiotics are ineffective, ciprofloxacin is prescribed intravenously.
pathogenetic therapy – the goal is to reduce general intoxication and remove toxins from human blood. To do this, intravenous infusion of colloidal and saline solutions is performed.
symptomatic therapy - used to alleviate the patient’s condition; for severe pain in the buboes, painkillers and anti-inflammatory drugs are used.

The prognosis for the treatment of cutaneous and bubonic plague is favorable (if adequate treatment is started early). In the case of the development of septic or pneumonic plague, the prognosis is unfavorable, mortality reaches 90-95%.

Discharge from the hospital is carried out no earlier than 4-6 weeks after the disappearance of symptoms of the disease, after triple bacteriological examination with negative results.

Prevention of plague

Prevention is an important measure aimed at preventing the spread of plague and the development of epidemics. There are nonspecific prevention and anti-epidemic measures in case of suspected plague.

Nonspecific prevention includes a number of activities:

obtaining and analyzing information on the status of plague in different countries;
medical and sanitary examination of vehicles and their passengers arriving from other countries;
identification, isolation and treatment of patients with suspected plague;
disinfection of vehicles that arrived from countries that are unfavorable in relation to the plague.

In natural plague foci, control of the number of rodents is carried out, their study to identify the causative agent of the plague, sick animals are destroyed.

Anti-epidemic measures are taken if at least one patient with suspected plague is detected:

the imposition of quarantine on the settlement, with a ban on the entry and exit of the population (except for medical workers) for 6 days;
drug prophylaxis of plague in contacts, the use of antibiotics for a course of at least 6 days, their isolation and observation;
Thorough disinfection is carried out in the plague outbreak;
contact people are injected with an anti-plague vaccine - a vaccine (EV strain) is applied to the skin, while immunity develops within 1 month and lasts 3-6 months.

It is worth remembering that the plague, even with the modern possibilities of medicine, is a very dangerous infectious disease with a high mortality rate. The circulation of the plague pathogen among animals does not make it possible to completely destroy this infection or transfer it to the category of controlled ones. Therefore, at the slightest sign of the plague, it is necessary to immediately seek medical help, because a person’s life depends on how early treatment is started.