Tick-borne encephalitis disease. Tick-borne encephalitis and how to treat it

viral infection, of natural origin, appearing during the period of spring, summer and early autumn.

Infection occurs during absorption into the skin and suction of blood from the human body (in the first minutes of suction) by a tick affected by the encephalitis virus.

Studies have shown that the duration of blood sucking from the human body is about several days, and the body weight of the insect, at the same time, increases many times over.

Infection with this infection is also possible when taking raw milk affected by the infection, or by-products made from a contaminated ingredient (milk).

The presence of the virus in the tissues of the human brain is determined, a few days after the bite (data from a clinical study), and is maximally observed on day 4.

The incubation period of tick-borne encephalitis depends on the method of infection (with a bite of 7-20 days, through food 4-7 days). Not everyone bitten by a tick gets sick. It all depends on the body's immune system.

How and when the disease occurs

Infection with tick-borne encephalitis affects people whose activities are carried out in the forest area (workers of timber industry enterprises, geologists, tourists, hunters), less, but still at risk, and urban residents visiting recreation parks, with forest plantations, dachas (garden and garden plots).

For infection, plant branches brought into the house from the forest, parks, summer cottages may also come up.

Ticks are considered carriers. living in the forest expanses, and affected by the infection. Clinical studies conducted on animals have shown that the affected animal (by a tick bite) experienced malaise, lethargy.

And after about 5 days, all the tissues of the organs were damaged by the virus. The accumulation of the virus was observed in the genital tract, intestines and salivary glands.

Pathogenesis

Differs in two reproductions:

1. The virus, when bitten by a tick, enters the blood cells. In them (inside) its development takes place, and when fully formed, it moves to the cell membrane, subsequently leaving it.
2. Lymph nodes, liver cells, spleen cells are affected, and then the virus enters the motor neurons of the spinal cord, the pia mater and the cells of the cerebellum.

Disease types

In modern medical literature, domestic authors, depending on the period and form of the course of the disease, and the number of deaths, it is permissible to divide infection viruses into the following types as dangers:

• west;
• Siberian;
• Far Eastern.

General signs of the disease

After a trip to an area dominated by a large number of deciduous trees and vegetation, the first signs of tick-borne encephalitis can be suspected when appearance:

Signs of tick-borne encephalitis in of people:

• the appearance of weakness in the limbs;
• the appearance of convulsions, numbness of the facial joints and necks;
• paralysis of individual parts of the muscles, then completely of the limbs.

The development of the disease is acute with distinctive signs:

• chills of the body and fever lasting from 2 to 10 days;
• general malaise of the patient;
• clouding of consciousness;
• different stages of deafness (different degrees).

As the body is covered by the infection, such symptoms of tick-borne encephalitis:

• severe headaches, accompanied by loss of consciousness, vomiting;
• rozhenie mucous membranes of the body (oral cavity, eyes (conjunctivitis develops));
• development of a coma with loss of time interval and space.

At the same time, patients observed:

• malfunctions of the cardiac system, cardiovascular insufficiency and arrhythmia appear;
• malfunctions of the digestive tract, stool retention is observed, can be detected during an internal check of the organs;
• enlargement of the liver and spleen.

At the same time, throughout the entire time of development of the infectious period, the patient has an elevated temperature within 40 degrees.

Despite the severe consequences of this disease, most often, the disease proceeds in a mild form, characterized by a slight fever.

Clinical forms of the disease

Experts distinguish between several forms of the disease, depending on the severity of its symptoms:

• feverish;
• meningeal;
• meningoencephalitic;
• polio;
• polyradiculoneuritic.

Symptoms depending on the form of the disease

The symptoms of infection are characterized appearance:

• fever;
• intoxication of the brain (damage to its gray matter), subsequently the development of encephalitis;
• damage to the brain and spinal cord, in particular its membranes, as a consequence of the development of diseases of meningitis and meningoencephalitis.

The listed diseases are dangerous because, if they are not treated in time, they lead to neurological and psychiatric complications, as well as to death.

Each form of the disease has its own specific first symptoms of tick-borne encephalitis.

Feverish form

Due to the mild course of the disease and a quick cure. Signs of an infection are:

• headache, weakness, nausea;
• the presence of fever, which fluctuates within 3-5 days.

meningeal form

A common form of the disease. The febrile state occurs with increased symptoms (listed below) and lasts from 7 to 14 days:

• headache (at the slightest movement), dizziness;
• nausea with single or repeated vomiting;
• pain in the eyes;
• there is lethargy and lethargy.

Meningoencephalitic form

Often found in the Far Eastern part of the country. It leaks and is heavy. Patients observed:

• delusional state with hallucinations;
• loss of orientation in time and place.

Missed treatment for this type of disease, leads to:

• damage to the brain by reference to the respiratory reflexes of the body;
• numbness of the facial muscles and muscles of the tongue;
• epileptic seizures (possible);
• gastric bleeding with bloody vomiting (in rare cases).

How is it different from the disease in adults. Special symptoms and methods of treatment of pathology in infants.

A severe and severe illness is alcoholic polyneuropathy, the treatment of which must be started in a timely manner, otherwise.

Polio form

observed in a third of patients. It begins with a general lethargy of the whole organism, observed for 1-2 days. Accompanied by:

• weakness in the limbs, which can later lead to numbness;
• characterized by pain in the neck.

Subsequently, with rapid, increasing violations of the motor functions of the body. The result is muscle atrophy.

Polyradiculoneuritic form

The patient's nervous system is damaged. Paralysis develops, starting from the legs and subsequently spreading to the entire body, covering the hands of the infected person.

Diagnostics

It is carried out by methods worn in medical literature and reference books titles:

Encephalitis as a disease is more common in children than in adults, occurring against the background of infectious diseases, may occur as a complication after vaccination.

The main symptoms and signs of tick-borne encephalitis in children include:

• the first sign of tick-borne encephalitis is a headache, expressed by a rise in body temperature;
• sleep disorders;
• disorders of the eyeball;
• disorders of the vestibular apparatus.

Treatment of the disease

There is no specific treatment for tick-borne encephalitis in humans. Applies drug therapy in which antiviral drugs are prescribed.

In case of damage to the nervous system, with the development of meningitis or encephalitis, the patient should be urgently hospitalized.

In the treatment of this disease, one can distinguish two ways:

• treatment of tick-borne encephalitis independently;
• help of a specialist.

Help self

It is carried out through traditional medicine.

If a tick is found on the body (it looks like a dark bulge, with a substance sticking out from under the skin (the back of the insect's body)), traditional healers recommend dropping a drop of vegetable oil or any alcohol on it, and leave for 15-20 minutes.

Under the paws sticking out above the skin of a person, bring a loop-like thread, and with smooth, slow, swaying movements, try to pull it out. The thread can be replaced with tweezers.

The extracted tick must be placed in any container and taken to a medical clinic to determine whether or not there is an infection in it.

Preferably after removing the insect from the skin, contact a specialist in the same hospital to undergo tests for the presence of infection in your body. Infectionists recommend, even if no infection is detected, to be observed by a doctor during the incubation period.

With the appearance of fever, skin rash, itching, an urgent consultation with a specialist is necessary.

Help from a specialist

If, nevertheless, due to a tick bite, an attempt to extract an insect was not crowned with a positive result, or there was a fear of doing something wrong action, specialist assistance is needed.

In the hospital, the tick will be removed from the skin of the patient, and the patient will be given an injection, intramuscularly, against the development of the disease.

Immunoglobulin is an expensive drug, due to the content of antibodies obtained from donated blood, previously vaccinated against tick-borne encephalitis. In addition to this medicine, there are a number of other antiviral drugs that can be prescribed by a doctor for preventive and therapeutic purposes.

• drug therapy;
• bed rest;
• rational diet.

Forecast

Data are based on 100 people - 100%:

1. Out of a hundred infected patients, complications (neurological and psychiatric) develop in 10-20 people.
2. Lethal outcome occurs for the European type: 1-2 people, for the Far Eastern type: 20-25 people. As a rule, death occurs after the onset of neurological symptoms for 5-7 days.

Preventive measures

1. The preparatory process is carried out in two stages. The first is in autumn, the second is in winter.
2. In case of sudden (extreme) cases, also in two stages, with breaks of two weeks. Immunity, as clinical studies show, develops 14-20 days after vaccination. After 9-12 months, 3 injections should be given.

Everyone, in order to prevent (prevention) must remember:

To date, tick-borne encephalitis is not incurable and, if detected in time, does not cause significant damage to the body.

The key in this case is timely detection of ticks and, therefore, you should especially carefully examine the surface of the skin (especially in children) after visiting the forest.

It should also be remembered that tick-borne encephalitis is not transmitted from one patient to another, it is not dangerous, like a viral disease, to others.

Video: What to do if you have had tick-borne encephalitis

A neurologist talks about what to do next if you were bitten by a tick and the patient suffered tick-borne encephalitis. Very helpful advice from Dr.

Ixodid ticks carry dangerous diseases, one of which is tick-borne encephalitis. In order to protect yourself from it, to recognize the onset of infection in time, it is important to know the mechanism of infection, what signs you should pay attention to, how symptoms develop, what consequences occur, how the disease is treated and what are the preventive measures.

What is tick-borne encephalitis

Tick-borne encephalitis is an infectious disease with natural foci. Ticks are carriers. It is isolated from 14 species of the genus Ixodes, and the main role is played by: Ixodes persulcatus and Ixodes ricinus.

Endemic areas: Siberia, Urals, Far East, Arkhangelsk, Leningrad, Irkutsk regions, about. Crimea, Perm, Primorsky Krai, rep. Tatarstan and others.

The peak incidence occurs in the warm season. This is due to the active visits by people to natural foci against the background of an increase in the activity of ticks.

Few people know what an encephalitic tick looks like. In outline, it resembles a spider. However, the structure is more primitive: instead of the typical division into cephalothorax and abdomen, the body consists of a trunk and mouth. The tick moves thanks to 4 pairs of short limbs. There is a hard shield on the back.

There are 2 mechanisms of human infection:

1. Transmissible - when biting. It has major epidemiological significance.
2. The alimentary mechanism is recorded extremely rarely. Infection occurs through unboiled milk from a diseased goat or cow with viremia.

The causative agent of encephalitis is a small RNA flavivirus coated with a protein coat. Its small size helps it penetrate various body barriers. Ultraviolet irradiation and high temperatures cause its destruction, and in the refrigerator, the encephalitis virus remains in products for up to 2 months. In the body of the ixodid tick, the pathogen quickly penetrates into all its organs with maximum accumulation in the digestive system. Therefore, the main danger to humans is precisely the bite of an encephalitis tick.

Entering the ovaries of females leads to the possibility of transmission of tick-borne encephalitis virions to offspring. Favorable conditions of the tick's body provide transphase transmission: the virus passes along with the tick, retaining the ability to infect. This mechanism is important for maintaining the focus of infection.

Spread of the virus in the body

The tick-borne encephalitis virus penetrates through the skin or mucous membrane of the gastrointestinal tract. The cells of the immune system are the first to meet it - macrophages, which are found in almost all organs. They specialize in capturing and digesting infectious, foreign agents, dead body cells.

The virus uses macrophages to recreate its own genetic material and assembly, then leaves them, spreading throughout the body hematogenously. The ability of the encephalitis virus to integrate into the DNA of host cells can lead to long-term asymptomatic carriage, and immune suppression leads to the chronic course of the disease. Also, the encephalitis virus can cause a dangerous slow infection with a long incubation, after which the first symptoms of the disease rapidly appear with a sharp deterioration.

The circulation of a virus in the blood is called viremia. It has 2 peaks: the first occurs during the initial propagation from the entrance gate. It does not last long, leads to the formation of foci of secondary reproduction in the liver, spleen, blood vessels, lymph nodes. The second peak falls at the end of the incubation period, when the encephalitis virus leaves the internal organs.

The first signs of the disease

The incubation period for tick-borne encephalitis is up to 30 days. When drinking milk, it is the shortest - up to several days. This period of time is dangerous with imaginary well-being, as well as the fact that it is subsequently difficult to associate the symptoms of an encephalitis tick bite with an infection. Painless redness can be seen on the skin - a trace of suction. The development of annular erythema indicates the presence of two tick-borne infections: encephalitis and borreliosis.

In some patients, the incubation period of encephalitis is replaced by nonspecific symptoms - a prodrome. These will be the first signs of encephalitis after a tick bite. They are often mistaken for the development of SARS. It:

• headache;
• weakness;
• fatigue;
• rise in temperature;
• irritability;
• sleep disorders;
• muscle pain;
• weakness in arms, legs;
• paresthesia of the skin of the neck, face.

Symptoms

Symptoms of tick-borne encephalitis indicate the spread of virions and help recognize the disease:

• hyperpyretic fever;
• chills;
• muscle pain;
• headache;
• redness of the face;
• slowing of the heartbeat;
• eye vascular injection;
• drop in blood pressure.
• abdominal pain, bloating, tongue with a white coating;
• hepato-, splenomegaly develop when the pathogen enters the organs.
• meningeal signs (symptoms of irritation of the meninges).

With damage to the central nervous system are added:

1. symptoms of shutdown, clouding of consciousness%
2. episyndrome;
3. malignant hyperthermia;
4. symptoms of local brain involvement.

The first signs of infection with damage to the motor neurons of the spinal cord look like flaccid paresis, paralysis.

Forms of tick-borne encephalitis

• place of introduction of the virus;
• duration of tick suction;
• the total number of ticks per person;
• properties of the encephalitis virus strain;
• properties of the human immune system.

The division of the disease into forms is conditional, since cases are known that begin with clinical signs of one form and then have an atypical development. Also, the symptoms of encephalitis after a bite may not be due to an asymptomatic course.

Let us consider in more detail the main forms of the disease:

feverish

Most victims of a tick bite develop a so-called febrile form of tick-borne encephalitis. It has the following features:

• sudden onset without prodrome;
• pale skin;
• muscle pain;
• pain in the eyeballs;
• a sharp rise in temperature to 39 degrees;
• severe intoxication;
• the appearance of symptoms of irritation of the membranes of the brain without inflammation (meningismus).

The elevated temperature persists for 6 days. CSF analysis is not indicative. This is the best quality option. At the exit, asthenic phenomena remain.

Minengial

The meningeal form is often diagnosed. The virus does not cross the membranes of the brain. Signs of tick-borne encephalitis are as follows:

• headache, dizziness;
• pain in the eyeballs, photophobia;
• cerebral vomiting without subsequent relief.

Patients are lethargic, positive persistent signs of irritation of the meninges are inhibited. The duration of the fever is about 3 weeks. Liquor contains a large number of lymphocytes, the content of proteins is increased.

Meningoencephalitic

The meningoencephalitic form appears when the tick-borne encephalitis virus crosses the blood-brain barrier. It is more severe due to the involvement of brain tissue. The fever reaches 40 degrees, its increase is accompanied by severe general somatic symptoms. The duration of the fever reaches 2-3 weeks. Meningoencephalitis can be diffuse or focal.

With diffuse lesions, the clinic is determined by cerebral disorders: epileptic seizures, dysphagia, violent crying, reflexes of oral automatism, delirium.

With a focal lesion, the cranial nerves are involved, unilateral paresis, episyndrome occur. The clinic appears on the 3rd - 5th day of illness.

Poliomyelitis

• muscle twitches;
• weakness in arms, legs;
• numbness;
• soreness;
• cerebral manifestations;
• flaccid paresis of the neck, muscles of the shoulder girdle, arms.

CSF analysis will show lymphocytosis. There are persistent consequences of tick-borne encephalitis: paresis, atrophy, malnutrition.

Tick-borne encephalitis with a two-wave course begins acutely, with meningeal and general somatic manifestations against the background of the first wave of fever. Analysis of the cerebrospinal fluid is not indicative, leukopenia, an increase in ESR are detected in the blood. The duration of the wave is up to 1 week. This is followed by a fever-free period of up to 2 weeks. The second wave of hyperthermia that follows is more severe. Lethargy, cerebral vomiting, meningeal signs, local manifestations are noted. A blood test will show leukocytosis; CSF pressure is increased, lymphocytosis is pronounced. This option often ends happily.

Polyradiculoneuritis

The polyradiculoneuritic form of tick-borne encephalitis occurs with damage to the peripheral nerves: pain in the arms, legs, numbness, paresthesia. Landry's palsy may join, starting in the legs or shoulder girdle, with involvement of the brain stem.

The severity of the infection can be mild, moderate, or severe. The type of course of tick-borne encephalitis is determined by the properties of the human body and the virus.

Few people know how encephalitis manifests itself in children. The infection manifests as fever. The tendency of children to generalized reactions leads to the difficulty of timely diagnosis of the disease. This means that the child's body cannot localize the infectious process due to insufficiently developed barriers. Therefore, there is an involvement of an increasing number of organ systems with the appearance of bright, but not allowing to establish the correct diagnosis, symptoms:

• stomach ache;
• urinary retention;
• fever that is not relieved by medication;
• vomit;
• sore throat;
• various neurological symptoms.

The course is severe, with frequent mental disorders. Encephalitis is dangerous due to the development of episyndrome, status epilepticus (epistatus). Episyndrome - the appearance of epileptic seizures due to damage to the brain by a virus.

Epistatus is a series of epileptic seizures, going one after another. In the interval between them, a person does not regain consciousness. This condition can cause swelling of the brain and lead to death. Due to the immaturity of the immune system, cases of a chronic course are frequent.

Consequences of tick-borne encephalitis

Some patients do not fully recover from the disease. Then various neurological disorders come to the fore.

The main consequences of encephalitis are:

• persistent headache;
• dizziness;
• ataxia;
• pathology of speech, hearing, vision;
• the formation of paresis, paralysis;
• impaired memory, attention;
• asthenic symptoms;
• psychotic disorders;
• heart failure;
• pneumonia.

Diagnostics

Diagnosis of tick-borne encephalitis includes a set of measures:

Important! If several ticks have been removed, they should be transported separately in signed jars.

1. Collection of complaints, medical examination data.
2. Laboratory research methods will help establish the diagnosis.

A general blood test will show leukocytosis, an increase in ESR.

With meningeal, focal symptoms, a spinal puncture with a study of the cerebrospinal fluid will allow you to find signs of inflammation: lymphocytosis, increased protein.

The diagnostic standard is a method (ELISA) that allows you to evaluate the appearance of Ig G, M and track the growth of titer in paired sera (at the beginning and end of the disease).

Detecting viral DNA fragments is possible thanks to the polymerase chain reaction (PCR) method. The material is blood, liquor.

Differential diagnosis is carried out with other neuroinfections, tuberculous meningitis, borreliosis.

Treatment

Important! A tick found on the body must be urgently removed and taken to the laboratory.

In the case of verification of the diagnosis, the etiotropic treatment of tick-borne encephalitis is carried out with the help of injections of a special immunoglobulin. It is used in people examined in the first few days after the tick is sucked. The scheme of administration is selected by the infectious disease specialist.

Patients need to be monitored, so the examination and treatment of encephalitis must be carried out in a hospital. Especially important is constant monitoring in children due to the danger of a sharp deterioration in the condition and death.

In the infectious diseases department, patients are provided with strict bed rest. Treatment includes:

• interferons;
• antipyretic;
• detoxification;
• vitamin preparations;
• neuroprotectors.

If necessary, the treatment is connected:

• hormones, diuretics to prevent cerebral edema;
• anticonvulsants;
• tranquilizers, neuroleptics;
• oxygen therapy.

Disease prevention

Disease prevention measures are divided into specific and non-specific.

Specific planned prevention of tick-borne encephalitis consists in timely vaccination. Vaccination is given to adults and children.

Emergency prevention of encephalitis is carried out by the introduction of immunoglobulin to all persons who applied after a tick bite before laboratory confirmation of the diagnosis.

Non-specific methods include:

1. The use of repellents.
2. When visiting a forested area, choose light-colored clothing that covers arms and legs, with tight-fitting cuffs, wearing a headdress with fields.
3. It is not recommended to sit on the grass, arrange parking, spending the night in areas with tall grass.
4. Regular inspections during walks for the timely detection of tick bites.
5. Mandatory boiling of milk.

Even a single and short contact with an encephalitis tick can provoke the development of the disease. Attentive attitude to your health will help to avoid terrible consequences and death.

Tick-borne encephalitis is an acute viral disease of the nervous system. The causative agent of the disease is a specific virus that more often enters the human body when bitten by a tick. Infection is possible when eating raw milk of sick animals. The disease manifests itself as general infectious symptoms and damage to the nervous system. Sometimes it is so severe that it can be fatal. People living in areas with a high prevalence of the disease are subject to preventive vaccination. Vaccination reliably protects against disease. From this article you will learn how tick-borne encephalitis proceeds, how it manifests itself and how to prevent the disease.

Tick-borne encephalitis is sometimes called differently - spring-summer, taiga, Siberian, Russian. Synonyms arose due to the characteristics of the disease. Spring and summer, because the peak incidence occurs in the warm season, when ticks are most active. Taiga, because the natural focus of the disease is mainly in the taiga. Siberian - due to the distribution zone, and Russian - due to the detection mainly in Russia and the description of a large number of strains of the virus by Russian scientists.

Causes of tick-borne encephalitis

The disease is caused by a virus belonging to the group of arboviruses. The prefix "arbo" means transmission by means of arthropods. The reservoir of the tick-borne encephalitis virus is the ixodid ticks that live in the forests and forest-steppes of Eurasia. The virus among ticks is transmitted from generation to generation. And, although only 0.5-5% of all ticks are infected with the virus, this is enough for the periodic occurrence of epidemics. In the spring-summer period, there is an increased activity of ticks associated with the cycle of their development. At this time, they actively attack people and animals.

The virus enters a person through the bite of an ixodid tick. Moreover, sucking a tick, even for a short period of time, is dangerous for the development of encephalitis, since the saliva of the tick, containing the pathogen, immediately enters the wound. Of course, there is a direct relationship between the amount of the pathogen that has entered the human bloodstream and the severity of the disease that has developed. The duration of the incubation period (the time from the entry of the pathogen into the body until the first symptoms appear) also directly depends on the amount of the virus.

The second way of infection is the consumption of raw milk or food products made from thermally unprocessed milk (for example, cheese). More often, the cause of the disease is the use of goat milk, less often - cows.

Another rare way of infection is the following: a tick is crushed by a person until it is sucked, but from contaminated hands the virus enters the oral mucosa if personal hygiene is not followed.

After entering the body, the virus multiplies at the site of penetration: in the skin, in the mucous membrane of the gastrointestinal tract. The virus then enters the bloodstream and spreads throughout the body. The preferred location for the virus is the nervous system.

Several types of virus have been identified that have a certain territorial attachment. A virus that causes less severe forms of the disease lives in the European part of Russia. The closer to the Far East, the worse the prognosis for recovery, and more deaths.

The incubation period lasts from 2 to 35 days. When infected due to the use of infected milk, it is 4-7 days. You should know that a patient with tick-borne encephalitis is not dangerous to others, since it is not contagious.

Tick-borne encephalitis begins acutely. First, general infectious signs appear: body temperature rises to 38-40 ° C, chills, general malaise, diffuse headache, aching and pulling pains in the muscles, weakness, and sleep disturbance occur. Along with this, there may be pain in the abdomen, sore throat, nausea and vomiting, redness of the mucous membrane of the eyes and throat. In the future, the disease can proceed in different ways. In this regard, there are several clinical forms of tick-borne encephalitis.

Clinical forms of tick-borne encephalitis

There are currently 7 forms described:

• feverish;
• meningeal;
• meningoencephalitic;
• polyencephalitic;
• polio;
• polioencephalomyelitis;
• polyradiculoneuritic.

Feverish form characterized by the absence of signs of damage to the nervous system. The disease proceeds like a common cold. That is, the temperature increase lasts 5-7 days, accompanied by general intoxication and general infectious signs. Then comes self-healing. No changes in the cerebrospinal fluid (as in other forms of tick-borne encephalitis) are found. If the tick bite was not recorded, then usually there is no suspicion of tick-borne encephalitis.

meningeal form is perhaps one of the most common. At the same time, patients complain of severe headache, intolerance to bright light and loud sounds, nausea and vomiting, pain in the eyes. Against the background of an increase in temperature, meningeal signs appear: tension in the muscles of the neck, symptoms of Kernig and Brudzinsky. Perhaps a violation of consciousness by the type of stunning, lethargy. Sometimes there may be motor agitation, hallucinations and delusions. The fever lasts up to two weeks. When carried out in the cerebrospinal fluid, an increase in the content of lymphocytes, a slight increase in protein are found. Changes in the cerebrospinal fluid last longer than clinical symptoms, that is, the state of health may improve, but the tests will still be poor. This form usually ends with complete recovery in 2-3 weeks. It often leaves behind a long-term asthenic syndrome, characterized by increased fatigue and fatigue, sleep disturbance, emotional disorders, and poor exercise tolerance.

Meningoencephalitic form characterized by the appearance of not only meningeal signs, as in the previous form, but also symptoms of damage to the substance of the brain. The latter are manifested by muscle weakness in the limbs (paresis), involuntary movements in them (from minor twitches to contractions expressed in amplitude). There may be a violation of the contraction of the facial muscles of the face, associated with damage to the nucleus of the facial nerve in the brain. In this case, the eye does not close on one half of the face, food flows out of the mouth, the face looks distorted. Among other cranial nerves, the glossopharyngeal, vagus, accessory, and hypoglossal nerves are more often affected. This is manifested by impaired speech, nasal voice, choking when eating (food enters the respiratory tract), impaired tongue movements, and weakness of the trapezius muscles. There may be a violation of the rhythm of breathing and heartbeat due to damage to the vagus nerve or centers of respiration and cardiac activity in the brain. Often with this form, epileptic seizures and disturbances of consciousness of varying severity, up to coma, occur. In the cerebrospinal fluid, an increase in the content of lymphocytes and protein is detected. This is a severe form of tick-borne encephalitis, in which cerebral edema may develop with the dislocation of the trunk and impaired vital functions, as a result of which the patient may die. After this form of tick-borne encephalitis, paresis, persistent speech and swallowing disorders often remain, which cause disability.

Polyencephalitic form characterized by the appearance of symptoms of damage to the cranial nerves on the 3-5th day of fever. The bulbar group is most often affected: glossopharyngeal, vagus, hypoglossal nerves. This is manifested by a violation of swallowing, speech, immobility of the tongue. The trigeminal nerves also suffer somewhat less often, which causes symptoms such as sharp pains in the face and its deformation. At the same time, it is impossible to wrinkle the forehead, close the eyes, the mouth twists to one side, the food pours out of the mouth. Tearing is possible due to constant irritation of the mucous membrane of the eye (because it does not close completely even during sleep). Even less often, damage to the oculomotor nerve develops, which is manifested by strabismus, a violation of the movement of the eyeballs. This form of tick-borne encephalitis can also be accompanied by impaired activity of the respiratory and vasomotor centers, which is fraught with life-threatening conditions.

Polio form has such a name in view of its similarity with. It is observed in approximately 30% of patients. Initially, there is general weakness and lethargy, increased fatigue, against which there are minor muscle twitches (fasciculations and fibrillations). These twitches indicate damage to the motor neurons of the anterior horns of the spinal cord. And then paralysis develops in the upper limbs, sometimes asymmetric. It can be combined with a violation of sensitivity in the affected limbs. Within a few days, muscle weakness captures the muscles of the neck, chest and arms. The following symptoms appear: “head hanging on the chest”, “bent stooped posture”. All this is accompanied by a pronounced pain syndrome, especially in the back of the neck and shoulder girdle. The development of muscle weakness in the legs is less common. Usually, the severity of paralysis increases for about a week, and after 2-3 weeks, an atrophic process develops in the affected muscles (muscles become exhausted, “lose weight”). Muscle recovery is almost impossible, muscle weakness remains with the patient for the rest of his life, making it difficult to move and self-service.

Polioencephalomyelitis form characterized by symptoms characteristic of the previous two, that is, simultaneous damage to the cranial nerves and neurons of the spinal cord.

Polyradiculoneuritic form manifested by symptoms of damage to peripheral nerves and roots. The patient develops severe pain along the nerve trunks, impaired sensitivity, paresthesia (sense of crawling, tingling, burning, and others). Along with these symptoms, ascending paralysis is possible, when muscle weakness begins in the legs and gradually spreads upward.

A separate form of tick-borne encephalitis is described, characterized by a peculiar two-wave course of fever. With this form, in the first wave of fever, only general infectious symptoms appear, resembling a cold. After 3-7 days the temperature returns to normal, the condition improves. Then comes the "light" period, which lasts 1-2 weeks. There are no symptoms. And then comes the second wave of fever, along with which there is a lesion of the nervous system according to one of the options described above.

There are also cases of chronic infection. For some reason, the virus is not completely eliminated from the body. And after a few months or even years, "makes itself felt." More often this is manifested by epileptic seizures and progressive muscle atrophy, which leads to disability.

The transferred disease leaves behind stable immunity.

Diagnostics

For the correct diagnosis, the fact of a tick bite in areas endemic for the disease is important. Since there are no specific clinical signs of the disease, serological methods play an important role in the diagnosis, with the help of which antibodies against the tick-borne encephalitis virus are detected in the blood and cerebrospinal fluid. However, these tests become positive starting from the 2nd week of illness.

I would especially like to note the fact that the virus can be found in the tick itself. That is, if you are bitten by a tick, then it must be taken to a medical facility (if possible). If a virus is detected in the tissues of a tick, preventive treatment is carried out - the introduction of a specific anti-tick immunoglobulin or the administration of Yodantipyrin according to the scheme.

Treatment and prevention

Treatment is carried out using various means:

• specific anti-tick immunoglobulin or serum of patients with tick-borne encephalitis;
• antiviral drugs are used: Viferon, Roferon, Cycloferon, Amiksin;
• symptomatic treatment consists in the use of antipyretic, anti-inflammatory, detoxifying, dehydration drugs, as well as agents that improve microcirculation and blood flow in the brain.

Prevention of tick-borne encephalitis can be non-specific and specific. Non-specific measures include the use of agents that repel and destroy insects and ticks (repellents and acaricides), wearing the most closed clothing, a thorough examination of the body after visiting a forested area, and eating heat-treated milk.

Specific prevention is emergency and planned:

• emergency is the use of anti-tick immunoglobulin after a tick bite. It is carried out only in the first three days after the bite, later it is no longer effective;
• it is possible to take Yodantipirin within 9 days after the bite according to the scheme: 0.3 g 3 times a day for the first 2 days, 0.2 g 3 times a day for the next 2 days and 0.1 g 3 times a day for the last 5 days ;
• planned prevention consists in carrying out vaccination. The course consists of 3 injections: the first two with an interval of a month, the last - a year after the second. This introduction provides immunity for 3 years. To maintain protection, revaccination is necessary once every 3 years.

Tick-borne encephalitis is a viral infection that initially occurs under the guise of a common cold.
It can go unnoticed by the patient, and can cause severe damage to the nervous system. The results of previous tick-borne encephalitis can also vary from complete recovery to permanent disability. It is impossible to get sick again with tick-borne encephalitis, since the transferred infection leaves a stable lifelong immunity. In areas endemic for this disease, it is possible to carry out specific prophylaxis, vaccination, which reliably protects against tick-borne encephalitis.

Survey TV, a plot on the topic "Tick-borne encephalitis":

Useful video about tick-borne encephalitis

Tick-borne encephalitis is a fairly common infectious disease. It usually has an acute course. Intoxication leads to damage to the nervous system, which can lead to paralysis.

It is a mistake to assume that, based on the name, tick-borne encephalitis can affect a person only after a tick bite. This is the prevailing version. However, the virus of this disease can also be located in the organisms of rodents and insectivores.

The most unpleasant thing is that domestic goats, cows or sheep can have the virus. They may have the virus, but they may not have symptoms of the disease. That is, these pets can be simple carriers. Human infection can occur through raw milk.

Tick-borne encephalitis is a viral pathology characterized by a transmissible mechanism of infection (with insect bites), as well as accompanied by febrile symptoms and damage to the tissues of the central nervous system.

Encephalitis is a disease of the brain. The suffix -it directly indicates that the disease is inflammatory in nature. Often, in the general case, the cause of encephalitis (inflammation of the brain) is difficult to establish.

However, in the case of a tick bite, the cause is obvious. It remains only to make sure that the bite was (here it is a tick that was removed from the skin) and establish the symptoms.

Here, in the case of receiving the tick-borne encephalitis virus through the infected milk of a pet, it will be more difficult to verify the cause.

The disease has a pronounced natural foci. The conditions for the existence of ticks are:

• favorable climate,
• essential vegetation,
• landscape.

Also, tick-borne encephalitis is characterized by seasonality.

A sick person is not a source of infection for others.

According to ICD10, tick-borne encephalitis is classified as A84.

Tick-borne encephalitis - causative agent

Tick-borne encephalitis viruses belong to the group of RNA-containing flaviviruses.

According to the genotype, tick-borne encephalitis viruses are divided into five types:

• Far Eastern
• western,
• Greek-Turkish,
• East Siberian
• Ural-Siberian.

For reference. The most common type of virus is the Ural-Siberian genotype of the pathogen.

The virus is quickly destroyed by boiling (within two to three minutes), during pasteurization, and also when treated with disinfectant solutions.

When dried and under freezing conditions, viral particles are able to retain their activity for a long time.

Attention. It should be noted that pathogens can persist in food products for a long time (especially in milk, butter, etc.).

Infection with tick-borne encephalitis

Tick-borne encephalitis is carried by ixodid ticks. Infection occurs mainly in a transmissible way: when biting a tick, as well as when combing the bite site, improper removal of the tick, etc.

Given that pathogens are resistant to hydrochloric acid, in isolated cases, alimentary (food) infection with tick-borne encephalitis may occur when consuming products containing viruses.

It should be noted that not all tick bites are accompanied by the development of an infectious process. According to statistics, the development of the disease after tick bites is recorded in approximately two to four percent of cases.

For reference. Infection of the ticks themselves with the encephalitis virus is observed when biting animals in which the viremic phase of the virus circulation is observed (the virus is in the blood).

In this regard, infection with viral particles is observed in approximately five percent of ticks. However, after a tick is infected with a virus, this type of virus circulates in its body for life and, in the future, is transmitted to the next generation of ticks. It is due to this that ixodid ticks are able to act as a natural reservoir of pathogens of tick-borne encephalitis.

The period of incubation of viruses in the human body is on average from ten to fourteen days (sometimes from one to thirty days).

For reference. A person cannot act as a source of infection (the virus is not transmitted from person to person).

risk factors for infection

The maximum activity of ticks is observed from mid-spring to the end of summer. In this regard, the maximum risk of infection is observed during these months.

For reference. Most often, tick-borne encephalitis affects people from twenty to sixty years old. The level of natural susceptibility to the disease is high and has no gender differences.

City dwellers, often resting in nature, get sick more often than rural dwellers.

- a dangerous viral disease that can lead to damage to the nervous system, paralysis and death. It is transmitted through the bites of ixodid ticks, parasites from the arthropod family that live in almost all climatic zones. To prevent complications and unpleasant consequences, it is necessary to determine the fact of a bite in time and take appropriate measures. How to understand what symptoms of the disease people have if they are bitten by a tick, after how many days the first signs of infection appear after a bite, and what to do if they are detected?

Ixodid ticks are representatives of the arthropod family, which has 650 species distributed throughout the world, except for the North Pole. This is one of the most hardy creatures, able to starve for a long time and endure temperature changes. In appearance, they are a bit like spiders - the size ranges from 0.5 to 2 cm, the body is round, red, brown or brown, it has 4 pairs of legs.

They stick to the skin of the victim and can remain on them for several days (sometimes 2-3 weeks), feeding on her blood. After that, they fall off on their own and hide for several weeks.

With an individual reaction to the saliva of a tick, an unexpressed allergic reaction of a local nature is possible - slight redness, inflammation and itching. If the tick has fallen off on its own, it is almost impossible to determine the fact of a bite, since no traces remain on the human skin.

A photo

The photo below shows what the place looks like after a tick bite, with characteristic signs on the human body.

How quickly does a disease manifest itself in a person

The incubation period of the disease in humans lasts from several days to two weeks, less often the first signs of infection appear a month after the bite. The clinical picture depends on the age and state of health of the person, as well as the type of virus that caused the infection. The classic picture includes two stages, each of which has certain symptoms.

Initial signs in children and adults

The danger of tick-borne encephalitis lies in the fact that there are no specific signs in the first stages. It is easy to confuse a sucked tick with a mole or a wart, and after falling off, a small red spot remains, on which a drop of blood can come out.

On the second day, redness, as a rule, increases, mild itching and a rash may occur, but in a healthy adult, after a bite, the signs are mild. If an infection has entered the wound, a slight suppuration may occur.

Tick ​​bites are most severe for the elderly, children, and allergy sufferers. In such cases, severe allergic reactions are possible up to Quincke's edema.

The first symptoms usually develop after a few days. They resemble SARS or a severe cold, but occur without respiratory manifestations (cough, runny nose, sore throat). Sometimes the first phase of tick-borne encephalitis is confused with severe poisoning, especially when it is accompanied by severe vomiting. The main differences are that the diarrhea characteristic of such conditions is absent in patients. Sorbents like activated charcoal also have no effect, since the pathogen is not in the digestive tract, but in the blood.

If you do not consult a doctor after the first symptoms appear, the disease will move into the second stage, which is characterized by more severe manifestations and often leads to serious complications.

First phase

In the first phase, there are no specific signs - patients have fever, headaches, muscle and joint pain, deterioration in general well-being.

1. Temperature rise. Usually, the temperature during infection rises to high numbers - 38-39 degrees. In rare cases, a clinical course of encephalitis is possible, accompanied by a slight fever - 37-37.5 degrees;
2. Pain. Pain in people infected with the virus is quite pronounced - they are localized in large muscle groups and joints. They resemble sensations after intense physical exertion or during inflammatory processes. In addition, there are sharp headaches without specific localization, spreading to the entire head;
3. Deterioration of well-being. Among the signs associated with intoxication of the body and a deterioration in general well-being include weakness, weakness, loss of appetite, sometimes nausea and vomiting. In some cases, patients have low blood pressure, tachycardia occurs, lymph nodes increase, and dizziness occurs.

The first phase of encephalitis lasts from 2 to 10 days (on average 3-4 days), after which remission occurs, and the symptoms recede. Between the first and second phases, it can take from several hours to several days. Sometimes the clinical course is limited to one phase, the first or second, and in some cases the clinical course is characterized by the presence of symptoms of both stages at the same time.

Second phase

The absence of symptoms does not mean recovery - the further course of the disease depends on the body's response to the virus. In 30% of cases, recovery occurs, but in 20-30% of patients, the second stage of encephalitis occurs, characterized by damage to the central nervous system.

Her symptoms include:

• stiffness of the neck muscles;
• intolerance to bright light and loud sounds;
• motor disorders up to paresis and paralysis;
• disturbances of consciousness, hallucinations, incoherence of speech;
• coma.

The severity of symptoms and the duration of the phases depend on various factors, including the course of the disease. "Western" encephalitis, which is common in Europe, has a favorable course and rarely leads to serious consequences.

The "Eastern" subtype (typical for the territory of the Far East), proceeds rapidly, and has a high lethality. It begins abruptly, with severe fever, headaches and severe intoxication, and damage to the nervous system develops after 3-5 days. Patients have severe damage to the brain stem, respiratory and circulatory disorders, as a result of which a fatal outcome often occurs. Sometimes encephalitis becomes chronic, and then periods of remission alternate with exacerbations.

In case of recovery (on its own or as a result of treatment), a person receives lifelong immunity. With a second bite, encephalitis infection is impossible, but do not forget that ticks carry about a dozen more dangerous ones, and the risk of infection with them remains.

Forms of the disease in humans

Symptoms and clinical course of tick-borne encephalitis depends on the form of the disease. To date, 7 varieties of the disease have been described, which are combined into two groups - focal and non-focal.

1. Feverish. It proceeds without damage to the nervous system, resembles SARS and does not cause serious consequences.
2. Meningeal. The most common form of the disease, accompanied by signs that resemble meningitis (stiff neck, photophobia, impaired consciousness).
3. Meningoencephalitic. The clinical course is characterized by meningeal signs and symptoms of damage to the medulla.
4. Polyencephalitic. It is accompanied by damage to the cranial nerves, and most often the pathological process affects the bulbar group - the hypoglossal, glossopharyngeal, vagus nerves.
5. Polio. The form of the disease, which is diagnosed in 30% of patients, and got its name because of the similarity with polio. Causes disruption of the motor neurons of the horns of the spinal cord.
6. Polioencephalomyelitis. It is characterized by manifestations characteristic of the two previous forms - simultaneous damage to the cranial nerves and neurons of the spinal cord.
7. Polyradiculoneuritis. Manifested by a disorder of the function of peripheral nerves and roots.

Non-focal (febrile and meningeal) forms of the disease are the easiest to proceed. The manifestations of the first do not differ from the common cold, and if the fact of a tick bite was not recorded, the person does not even suspect that he had been ill with tick-borne encephalitis. The meningeal form can be quite difficult, but it is also almost always cured completely, without serious health consequences.

In other cases (with focal forms), the symptoms and prognosis depend on the clinical course of the disease - in mild cases, complete recovery is possible, in severe cases, the patient's disability or death is possible.

What does the patient look like?

External manifestations of tick-borne encephalitis are absent - in the first phase it is impossible to distinguish it from other diseases without clinical studies. In bitten people, the face turns red, sometimes there are pinpoint hemorrhages on the whites of the eyes and mucous membranes, tearing. In severe cases, intoxication and weakness are so pronounced that the person is unable to tear his head off the pillow. In the vast majority of cases, there is no rash throughout the body - a similar symptom is observed only in allergy sufferers, young children and people with weakened immune systems.

Below are photos of people after being bitten by an encephalitis tick.

Changes in appearance and behavior when a person is bitten by an infected tick appear in the second stage, when the virus infects the nervous system. Tick-borne encephalitis can be recognized by the following manifestations:

• motor agitation, hallucinations, delusions;
• violation of the function of facial muscles (the face looks skewed, one eye does not close, speech is disturbed, the voice becomes nasal);
• epileptic seizures;
• change and constant lacrimation due to irritation of the mucous membrane, strabismus, impaired movement of the eyeballs;
• slight muscle twitching, usually occurring after physical exertion, sometimes even minor;
• a specific posture with a bent back and a head hanging on the chest (the reason is the weakness of the muscles of the neck, chest, arms);
• weakness of the lower extremities, muscle atrophy (very rare).

Even in the presence of characteristic symptoms, an accurate diagnosis can be made only after a comprehensive examination of the patient. Signs of tick-borne encephalitis resemble manifestations of other diseases associated with damage to the nervous system, tumor processes and other pathologies.

REFERENCE! A patient with tick-borne encephalitis does not pose a danger to others at any stage, since in the human body the virus goes through the final stage of development and is unable to be transmitted further.

What are the consequences after the disease

Tick-borne encephalitis can cause serious complications, even death. With the western subtype of the disease, the mortality rate is 2-3%, with the Far Eastern variety - about 20%.

With irreversible damage to the nervous system, the patient may remain a partial or complete invalid. People who have had to deal with complications of tick-borne encephalitis experience paralysis, muscle weakness, epileptic seizures, and persistent speech disorders.

It is impossible to restore the disturbed functions of the body, so a person and his relatives will have to adapt to their condition and completely change their lifestyle.

Diagnostics

To make a diagnosis in case of suspected tick-borne encephalitis, modern methods of examining the patient's blood and cerebrospinal fluid are used. With the help of serological testing with the determination of specific antibodies to the virus, it is possible to determine not only the fact of infection, but also the clinical features of its course. Sometimes the PCR method and virological examination are used, but they are considered less accurate and informative.

If the tick can be removed entirely, it is placed in a clean container and delivered to the laboratory, where a test is carried out for the presence of the virus antigen. This option for detecting infection is considered optimal, since treatment can be started immediately, before the first symptoms appear.

IMPORTANT! The most dangerous forms of tick-borne encephalitis are considered, characterized by damage to the cranial nerves and medulla. If the activity of the respiratory center and the vascular system is disturbed, a serious threat to human life arises.

Treatment

There is no specific treatment for tick-borne encephalitis. For several days after the bite, the patient can be given drugs containing immunoglobulins, which have a pronounced therapeutic effect and prevent complications.

If symptoms of damage to the human nervous system occur, it is urgent to be taken to a hospital where supportive and symptomatic therapy is carried out.

Corticosteroids, anticonvulsants, drugs that normalize the functions of the nervous and cardiovascular systems, and vitamins are used for treatment. In severe cases, tracheal intubation and mechanical ventilation are necessary. During the rehabilitation period, patients are prescribed massage, physiotherapy exercises, spa treatment.

Protecting yourself from tick-borne encephalitis is much easier than dealing with the symptoms and complications of the disease. To do this, you need to take precautions when walking in nature, and after returning home, carefully examine the whole body. If, after spending time in a forest or park, a person has a fever and his health worsens, you should immediately consult a doctor.