Crimean hemorrhagic fever health bulletin. Hemorrhagic fever symptoms

Crimea-Congo hemorrhagic fever is an acute zoonotic natural focal viral infection with a transmissible transmission mechanism, characterized by severe hemorrhagic syndrome and two-wave fever.

Crimean-Congo hemorrhagic fever was first described on the basis of materials from an outbreak in Crimea (Chumakov M.P., 1944-1947), therefore it was called Crimean hemorrhagic fever (CHF). Later, cases of a similar disease were registered in the Congo (1956), where in 1969 a virus similar in antigenic properties to the Crimean hemorrhagic fever virus was isolated. To date, the disease has been registered in Europe, Central Asia and Kazakhstan, Iran, Iraq, the United Arab Emirates, India, Pakistan, and African countries (Zaire, Nigeria, Uganda, Kenya, Senegal, South Africa, etc.).

Epidemiology of Crimea-Congo hemorrhagic fever

Reservoir and sources of infection- domestic and wild animals (cows, sheep, goats, hares, etc.), as well as more than 20 species of ixodid and argasid ticks, primarily pasture ticks of the genus Hyalomma. The main reservoir of infection in nature is small vertebrates, from which livestock becomes infected through ticks. The contagiousness of animals is determined by the duration of viremia, which lasts about a week. Ticks represent a more persistent reservoir of infection due to the possibility of sexual and transovarial transmission of the virus. High contagiousness of sick people has been noted. In animals and humans, the virus is found in the blood during intestinal, nasal and uterine bleeding, as well as in secretions containing blood (vomit, feces).

Transmission mechanisms- transmissible (from ixodid tick bites), as well as contact and aerogenic. When infected from humans or animals, the main mechanism of transmission is contact due to direct contact with the blood and tissues of infected animals and people (intravenous infusions, stopping bleeding, artificial respiration using the mouth-to-mouth method, taking blood for research, etc.). The aerogenic mechanism of infection transmission has been described during intra-laboratory infection of personnel during emergency situations during centrifugation of virus-containing material, as well as under other circumstances if the virus was contained in the air.

Natural sensitivity of people high. Post-infectious immunity lasts for 1-2 years after the illness.

Basic epidemiological signs. Crimea-Congo hemorrhagic fever disease is distinguished by its pronounced natural focality. In countries with warm climates, foci of infection in the form of outbreaks and sporadic cases are confined mainly to steppe, forest-steppe and semi-desert landscapes. The incidence rate is associated with the period of active attack by adult ticks (in the tropics - year-round). Men aged 20-40 years are most often affected. Cases of infection predominate among persons of certain professional groups - livestock farmers, agricultural workers, veterinary and medical workers. Nosocomial outbreaks of infection and intra-laboratory infections have been described.

Pathogenesis of Crimea-Congo hemorrhagic fever

The pathogenesis of Crimea-Congo hemorrhagic fever is similar to other viral hemorrhagic fevers. Characterized by the development of intense viremia, thrombocytopenia, lymphopenia in the acute stage of the disease, as well as an increase in AST, as with most viral hemorrhagic fevers, the increase in ALT is less pronounced. In the terminal stage, liver and kidney failure and acute cardiovascular failure are observed. An autopsy reveals eosinophilic infiltration in the liver without a pronounced inflammatory reaction, necrotic changes in the spleen and lymph nodes. The development of massive bleeding is possible. DIC syndrome is recorded in the terminal phase, its genesis is not clear. As with other viral hemorrhagic fevers, there are degenerative processes in muscle tissue and weight loss.

Symptoms of Crimea-Congo hemorrhagic fever

Incubation period of Crimea-Congo hemorrhagic fever after a bite of an infected tick it lasts 1-3 days; after contact with blood or infected tissues it can last up to a maximum of 9-13 days. Symptoms of Crimea-Congo hemorrhagic fever vary from mild to severe.

Laboratory diagnosis of Crimea-Congo hemorrhagic fever

Laboratory diagnosis of Crimea-Congo hemorrhagic fever is carried out in specialized laboratories with an increased level of biological protection. Characteristic changes in the hemogram are pronounced leukopenia with a shift to the left, thrombocytopenia, increased ESR. A urine test reveals hypoisosthenuria and microhematuria. It is possible to isolate the virus from blood or tissue, but in practice the diagnosis is more often confirmed by the results of serological reactions (ELISA, RSK, RNGA, NRIF). IgM class antibodies in ELISA are determined within 4 months after the disease, IgG antibodies - within 5 years. It is possible to determine virus antigens in ELISA. In recent years, polymerase chain reaction (PCR) has been developed to determine the genome of the virus.

Treatment of Crimea-Congo hemorrhagic fever

Hospitalization and isolation of patients is mandatory. Treatment of Crimea-Congo hemorrhagic fever is carried out in accordance with the general principles of treatment of viral hemorrhagic fevers. In some cases, a positive effect was noted from the administration of 100-300 ml of convalescent immune serum or 5-7 ml of hyperimmune equine immunoglobulin. In some cases, good effect can be obtained from the use of ribavirin intravenously and orally (see Lassa fever).

Prevention of Crimea-Congo hemorrhagic fever

When hospitalizing patients, you should strictly follow the requirements for the prevention of nosocomial infections and personal prevention of employees, and be careful when performing invasive procedures. Persons who have come into contact with the patient's blood and secretions, as well as sectional material, are administered a specific immunoglobulin as an emergency prophylaxis. Deratization and acaricidal measures in natural foci are not very effective, since the vectors are numerous and widespread. Particular attention is paid to protecting people from ticks. Personal prevention measures include wearing protective clothing, impregnating clothing, tents and sleeping bags with repellents. According to epidemiological indications, it is recommended to use a formaldehyde-inactivated vaccine from the brains of infected white mice or suckling rats, but a reliable and effective vaccine against Crimean-Congo fever does not yet exist.

Medical workers who have been in contact with people who are sick or suspected of this disease, as well as biomaterial from them, must be monitored for three weeks with daily thermometry and careful recording of possible symptoms of Crimean-Congo hemorrhagic fever. The outbreak area is disinfected and contact persons are not separated.

There are diseases that normally only affect animals. However, in some cases, such ailments can be transmitted to humans, bringing many unpleasant symptoms and sensations, and sometimes causing death. Just such diseases include Crimean hemorrhagic fever, which most experts call Crimean-Congo. This pathological condition can occur not only in the Crimea, but also in the Caucasus, as well as in the Stavropol Territory and the Astrakhan Region. Let's talk about the manifestations of this disease, as well as methods for its correction and prevention.

The Crimean fever virus is carried by various domestic animals, including sheep and goats, as well as cows, etc. The disease spreads to humans, either through direct contact with the blood of an affected animal or through a tick bite. Quite often, this disease is recorded in people who are directly involved in animal husbandry.

How does Crimean hemorrhagic fever manifest? Symptoms of the disease

After the virus enters the body, there is a fairly short incubation period, which can range from one day to a couple of weeks. The illness starts quite suddenly, the patient experiences severe chills, and his body temperature rises up to forty degrees. Despite this, the pulse does not accelerate, but rather slows down to almost forty beats, which is classified as bradycardia.

In the first few days of the development of the disease, the patient experiences manifestations of general intoxication of the body. Patients complain of headaches, a feeling of fatigue and weakness, they are bothered by painful sensations in the epigastric region, as well as aches in the joints and muscles.

In some cases, these symptoms are accompanied by catarrhal phenomena in the upper respiratory tract. A fairly common manifestation of hemorrhagic fever of this type at the initial stage of development is repeated vomiting, which greatly debilitates the patient. This symptom is not at all related to food consumption, which doctors usually associate with peculiar lesions of the stomach, as well as the autonomic nervous system in the solar plexus area.

Before the disease enters the second phase (directly hemorrhagic), body temperature drops for a couple of days, after which it rises again against the background of the formation of hemorrhagic rashes. At first, the rash is localized in the armpits, as well as on the surface of the elbows and on the inside of the thigh. Afterwards, such rashes spread throughout the entire skin and mucous membranes, including the conjunctiva. The patient's face turns pale, becomes puffy, cyanosis, acrocyanosis, and noticeable hemorrhages in the skin appear on it. The classic manifestation of this phase of hemorrhagic fever is bleeding of various locations, bleeding gums are observed and hemoptysis occurs. At this stage, bradycardia disappears, giving way to tachycardia, blood pressure decreases significantly, and oliguria appears.

How and with what is Crimean hemorrhagic fever eliminated? Treatment of the disease

All patients suspected of developing Crimean hemorrhagic fever are required to be hospitalized. First of all, they are given symptomatic treatment, which involves taking antipyretic drugs.

If the temperature rises above 38.5 degrees, the drugs of choice are ibuprofen and paracetamol. When these data increase to forty degrees and above, doctors usually administer promethazine intravenously or intramuscularly, sometimes combining it with chlorpromazine.

In order to correct the water-electrolyte balance and remove toxins from the body, infusion therapy is practiced, using a solution of albumin, dextran, sodium chloride, as well as hemodez, etc.

To stop and prevent bleeding, aminocaproic acid is administered in the form of a solution, as well as solutions of ascorbic acid and ethamsylate.

Treatment of Crimean hemorrhagic fever involves immunocorrective therapy. This specific therapy involves the administration of immune serum, as well as hyperimmune gammaglobulin.

In mild cases of the disease, the use of loratadine and promethazine is practiced as hyposensitizing therapy; if the disease is severe, then hydrocortisone, as well as prednisolone or dexamethasone, are used for this purpose. Ouabain is commonly used to correct heart failure. If necessary, intensive care techniques or resuscitation can also be used.

How is Crimean hemorrhagic fever prevented? Disease Prevention

The main measure for the prevention of Crimean hemorrhagic fever is the fight against ticks - carriers of the causative agent of the disease. For this purpose, special chemical elements are used - acaricides.

All people who live in an area of ​​possible infection should protect themselves from ticks and prevent their bites. When working with animals or their tissues, it is worth using various protective clothing, including gloves. Before animals go to slaughterhouses, they should be kept in quarantine or treated with pesticides.

When working with people sick with this disease, you should avoid close contact, wear protective clothing, and also maintain personal hygiene - wash your hands, etc.

With proper treatment of Crimean hemorrhagic fever, the patient’s chance of recovery significantly increases.

text_fields

text_fields

arrow_upward

Incubation period lasts 2–14 days (average 3–5 days). The disease can occur in mild, mild, moderate and severe forms. In addition to the incubation period, there are 3 periods of the disease: initial, height, or hemorrhagic phase, and outcome.

Initial period lasts 3–6 days and is characterized by sudden chills, a rapid increase in body temperature to 39–40°C, widespread myalgia and arthralgia, severe headache, and often pain in the abdomen and lumbar region. A number of patients have a positive Pasternatsky symptom. Common symptoms include dry mouth, dizziness and repeated vomiting.

Patients are usually excited, their face, mucous membranes, neck and upper chest are hyperemic, their lips are dry, and a herpetic rash is often noted. Arterial hypotension is characteristic, the pulse often corresponds to body temperature or is somewhat slow. Hematological changes during this period are manifested by leukopenia with a neutrophilic shift to the left, thrombocytopenia, and increased ESR.

High period The illness lasts 2–6 days, often develops after a short-term, within 1–2 days, decrease in body temperature. In this phase of the disease, a pronounced hemorrhagic syndrome is detected in the form of a petechial rash on the lateral areas of the body, in the area of ​​​​large folds and limbs. In severe forms of the disease, purpura, ecchymosis are observed, and bleeding from the gums, nose, stomach, uterus, intestines, and lungs is possible.

Patients are depressed and pale; they have acrocyanosis, tachycardia and arterial hypotension; possible delirium. In 10–25% of cases, meningeal symptoms, agitation, convulsions are observed, followed by the development of coma. The liver is usually enlarged, and some patients show signs of hepatargia. Oliguria, microhematuria, hypoisosthenuria, and azotemia often develop. Sometimes there are complications in the form of pneumonia, pulmonary edema, thrombophlebitis, acute renal failure, shock. The duration of fever is 4–8 days.

Convalescence period long-term, up to 1–2 months, characterized by an asthenic symptom complex. In some patients, performance is restored over the next 1–2 years.

In endemic areas, abortive forms of the disease without pronounced hemorrhagic syndrome are often observed.

Laboratory tests, in addition to characteristic hematological changes, reveal an increase in hematocrit, residual nitrogen, aminotransferase activity, and signs of metabolic acidosis. Significant thrombocytopenia and high hematocrit values ​​may indicate a poor prognosis.

Crimean hemorrhagic fever, also called Crimean-Congo hemorrhagic fever or CCHF, is an acute infectious disease that occurs in 2 stages, accompanied by muscle and headaches, intoxication of the body, hemorrhages on the skin and internal organs, increased bleeding (hemorrhagic syndrome) . The Crimean-Congo fever virus is transmitted through tick bites. The fever was first learned about in 1944, respectively, in Crimea. A little later, the same clinical picture and the same symptoms were recorded by doctors in the Congo, hence the name. And in 1945, scientists were able to identify the causative agent of the disease.

The method of transmission of Crimean hemorrhagic fever is most often transmissible, that is, the method in which the infection is in the blood or lymph. In addition, the disease is transmitted by contact - for example, when a tick is crushed on the skin and infected particles get on the wounds; aerogenously – in the presence of a virus in the air; Infection in medical institutions occurs due to poor handling of instruments and secondary use of syringes and needles.

The virus infects the endothelium of blood vessels, causing disorders of blood clotting and blood formation, and can also cause disseminated intravascular coagulation syndrome (a hemorrhagic diathesis that causes excessive acceleration of intravascular coagulation). This disease leads to hemorrhages in the internal organs, the central nervous system, as well as bruising on the skin and mucous membranes.

Symptoms

The asymptomatic period, which is called the incubation period, of Crimea-Congo fever takes on average from 2 to 14 days. The length of the incubation period varies depending on the method of infection of the patient. If the infection occurred due to the bite of a blood-sucking insect, then the incubation period lasts 1-3 days, if transmitted by contact, then 5-9 days. Symptoms can range from mild to very severe. To this we must add that the disease occurs in 3 periods - incubation, initial (pre-hemorrhagic) and hemorrhagic.

The initial period occurs after the incubation period. The temperature rises to 40 degrees, dizziness, chills, and weakness begin. Patients are worried about headaches, discomfort in the abdomen and lower back, myalgia (muscle pain that occurs due to cell hypertonicity both in a calm and tense state) and arthralgia (pain in the joints in the absence of visible joint damage). Also symptoms are: dry mouth, increased blood flow to the conjunctiva, neck, mucous membrane of the pharynx and face, possible nausea and vomiting. Possible surges of aggression, anger, and excitement. These symptoms are replaced by the opposite - fatigue, drowsiness, depression. Before the start of the second wave of fever, the body temperature drops to subfebrile (a constant temperature that ranges from 37.1 to 38.0 degrees).

Hemorrhagic period - at the height of Crimea-Congo fever, hemorrhagic manifestations begin to appear. Among them: exanthema (petechial rash on the skin), enanthema (rash that occurs on the mucous membranes of the mouth), purpura or ecchymoses, bruising after injections, coughing up blood, nosebleeds, in extreme cases, abdominal bleeding occurs, which can be gastric, uterine or pulmonary . Inflammatory damage to the lymph nodes or an increase in the size of the liver may appear. Other symptoms include convulsions, coma, and confusion.

Consequences of Crimean hemorrhagic fever

With timely treatment and the absence of complications, hemorrhages (bleeding) disappear after 4-7 days. The recovery process begins on the tenth day of the disease and takes approximately one and a half months. Psychopathic disorder after illness lasts more than a year. The positive factor is that immunity to infection appears, which persists for another 1-2 years after the disease.

Complications after Crimea-Congo fever:

• pulmonary edema;
• renal and liver failure;
• thrombophlebitis (inflammation of the internal venous wall with the formation of a blood clot);
• infectious-toxic shock;
• pneumonia.

There is a risk of death, it is 4-30%; if death occurs, it occurs in the second week of the disease.

Diagnosis of Crimean hemorrhagic fever

Diagnosis is based on the following:

1. Clarification of epidemiological data - the possibility of the patient staying in places with an increased risk of infection, seasonality is taken into account.
2. Study of clinical signs - symptoms and features of the course of the disease.
3. Laboratory test results - general urine and blood analysis, enzyme immunoassay, PCR (polymerase chain reaction) and RNHA (indirect hemagglutination reaction).

During diagnosis, a lack of red blood cells, leukopenia, thrombocytopenia, and neutropenia are detected in the patient’s blood.

The examination and all contacts with patients must comply with strict sanitary standards and infection safety.

Treatment of Crimean hemorrhagic fever

Even if Crimea-Congo fever is suspected, immediate hospitalization and isolation of the patient is necessary.

It is important for the patient to adhere to bed rest and diet; in combination, the patient is prescribed vitamin therapy.

As treatment, it is possible to use convalescent immune serum and hyperimmune γ-globulin. In addition, the patient is prescribed antiviral drugs that have a therapeutic effect: alpha interferon, ribavirin.

At the beginning of treatment, hemostatic and detoxification therapy is carried out, and blood transfusions are performed. When diagnosing infectious-toxic shock, glucocorticosteroids are prescribed.

Prognosis for Crimean hemorrhagic fever

If the fever develops rapidly, moreover, has acute symptoms, the risk becomes serious. Serious complications can occur, and in extreme cases, death. But most often, with timely and correct treatment, the prognosis is favorable.

Prevention of Crimean hemorrhagic fever

The main way to protect yourself from Crimea-Congo fever is to beware of tick vector bites. To do this, you need to use sprays and ointments against ticks, wear protective clothing and shoes, use repellents, and regularly conduct self-examinations if you are outdoors.

Hospitals must adhere to hygiene and sanitary standards. This includes high-quality processing of instruments, the use of only disposable syringes, and compliance with the rules when working with the patient’s secretions and blood. There is no vaccine against Crimean hemorrhagic fever.

To summarize, CCHF is a severe viral disease that requires immediate hospitalization and treatment. The disease is most often transmitted by ticks. If you follow some rules, infection can be avoided. Particular caution must be observed in medical institutions; sometimes control can be taken into your own hands, since the human factor can never be ruled out: even doctors can be negligent in their work. It is worth noting that this disease is highly not recommended to be treated with traditional methods; at best they are useless, at worst they are harmful. Self-medication is also not allowed, as this can cause irreparable harm to your condition.

Among the first signs of the disease are:

• severe weakness from the first days of the disease;
• increased body temperature (39-40° C). The fever has a “two-humped” character: 3-4 days after a sharp increase, the body temperature drops to normal values, and then there is a repeated sharp rise, which coincides in time with the appearance of a hemorrhagic rash on the body;
• chills (shivering) when body temperature rises;
• severe headache, dizziness;
• pain in muscles, joints (especially lower back pain);
• nausea, vomiting;
• lack of appetite;
• no changes at the site of the tick bite.

• A hemorrhagic rash appears on the skin and mucous membranes (mainly on the chest and abdomen). The rash consists of pinpoint hemorrhages. Then, at the site of pinpoint hemorrhages, larger scarlet spots appear in the form of bruises, hematomas (cavities containing coagulated blood of a purple or bluish hue);
• bleeding develops (nosebleeds, bloody discharge from the eyes, ears; bleeding of the gums and tongue is noted; gastric, intestinal and uterine bleeding develops, hemoptysis);
• arterial (blood) pressure decreases;
• there is a decrease in heart rate;
• Confusion, hallucinations, and delirium are possible.

• normalization of body temperature;
• disappearance of hemorrhagic manifestations;
• maintaining general weakness;
• apathy (depressed mood);
• rapid fatigue;
• irritability;
• the duration of the recovery period is from 1 month to 1-2 years.

Incubation period

From 1 to 14 days after the tick bite (usually 2-9 days).

Forms

• Crimean hemorrhagic fever with hemorrhagic syndrome: a typical clinical picture is observed with hemorrhagic rashes (bleedings into the skin), bleeding of varying severity.
• Crimean hemorrhagic fever without hemorrhagic syndrome sometimes occurs: there is no second wave of rise in body temperature, hemorrhagic syndrome in the form of bleeding does not develop.

Causes

Human infection with Crimean fever is possible in three ways.

• Most people become infected by transmission(via a tick bite). Ticks, in turn, become infected when feeding (blood sucking) on ​​large and small livestock and subsequently infect healthy individuals or humans.
• Contact way:
  • ​ upon contact with damaged skin and mucous membranes of blood infected with Crimean hemorrhagic fever (animal or human);
  • when crushing ticks (in this case, the pathogen enters the body through microtraumas, cracks and sores on the skin).

• Nutritional route(when consuming raw (unpasteurized) milk from an infected animal, usually goat).

Natural foci of the disease are located in forest-steppes, steppes, semi-deserts, that is, places used for grazing livestock.

Diagnostics

• Analysis of epidemiological history (establishing the fact of a tick bite in an area characterized by this disease).
• Analysis of complaints and medical history (presence of tick bite marks on the body, sudden increase in body temperature, hemorrhagic rash (bleeding into the skin), bleeding, decreased heartbeat, etc.).
• Virological diagnostics. Isolation of a virus from human saliva and/or blood, its introduction into the body of laboratory animals, followed by observation of changes in their condition and the possible development of a characteristic infectious process.
• Serological diagnosis is the determination of antibodies in the patient’s blood to a pathogen (antibodies are specific proteins of the immune system, the main function of which is to recognize the pathogen (virus or bacteria) and its further elimination).
• Consultation is also possible.

Treatment of Congo-Crimea hemorrhagic fever

Patients with hemorrhagic fever are subject to mandatory hospitalization. In some cases, antiviral drugs are prescribed, but in general therapy is limited to symptomatic treatment:

• administration of immune plasma (donor blood plasma taken from people who have already had this disease and have immunity (protection) against this virus);
• compliance with bed rest (limit physical activity, even walking);
• taking semi-liquid, easily digestible food;
• transfusion of donor platelets (blood cells responsible for blood clotting) in order to normalize blood clotting function;
• in case of severe intoxication (weakness, nausea) and dehydration, administration of saline solutions or glucose solution or vitamin therapy (solutions of ascorbic acid, B vitamins and vitamin PP) are prescribed;
• hemodialysis (“artificial kidney”) - cleansing the blood of toxins produced by the virus;
• antipyretic drugs (to reduce body temperature);
• antibiotics in case of bacterial infection.

Complications and consequences

Against the background of Crimean hemorrhagic fever, the following are possible:

• severe gastrointestinal, nasal, uterine (in women) bleeding;
• thrombophlebitis (inflammation of the vein wall and the formation of blood clots in the lumen of the vessel with further disruption of blood circulation);
• infectious-toxic shock (drop in blood pressure and death as a result of poisoning of the body with viral toxins);
• swelling of the brain;
• pulmonary edema (one of the main causes of death along with liver and urinary failure);
• acute renal failure (serious impairment of kidney function up to their loss);
• acute liver failure (death of liver cells and, as a result, impaired neutralization of toxic substances, jaundice, bleeding).

• pneumonia (pneumonia);
• sepsis - a serious condition caused by the circulation of a pathogen in the bloodstream with the formation of foci of purulent inflammation in various organs (for example, when the septic process spreads to the meninges (purulent meningitis), insomnia, irritability, hearing and vision impairment may develop).

Prevention of Congo-Crimea hemorrhagic fever

When in a natural area:

• when going to the forest, park or country house, wear long sleeves, tuck your trousers into your boots, and be sure to wear a hat;
• use liquids, aerosols, ointments (repellents) that repel ticks and other insects. The procedure for applying repellents must be repeated every 2-3 hours; other creams (sunburn, cosmetics, etc.) can be used together with repellents: this does not affect their effectiveness in any way;
• stay away from bushes and tall grass, as this is where ticks live;
• upon returning from the forest, carefully examine yourself, ask another person to examine you (pay special attention to the border of the scalp, natural folds of the skin (for example: armpits, behind the ears);
• also inspect pets that may bring ticks into the house;
• do not consume unpasteurized milk;
• if a tick bite is detected, seek medical help;
• preventive vaccination (vaccination) for persons who are going to enter the territory of the South of Russia.

Additionally

• Crimean hemorrhagic fever develops as a result of the penetration of a virus from the arbovirus family, the Congo virus, into the human body.
• The natural reservoir of the virus is:
  • wild animals (wood mouse, small gopher, brown hare, long-eared hedgehog);
  • domestic animals (sheep, goats, cows);
  • mites (genus Hyalomma).

• In Russia, the incidence is characterized by seasonality with a peak from May to August. Infection occurs in the spring-summer period (peak in June - July).
• Annual outbreaks of Congo-Crimea fever in some regions of Russia (in the Krasnodar and Stavropol Territories, Astrakhan, Volgograd and Rostov regions, in the republics of Dagestan, Kalmykia and Karachay-Cherkessia) are due to the fact that in recent years the necessary treatment of livestock against ticks has not been carried out.