Encephalitis tick: description with photo, symptoms of a bite in humans

What types of ticks carry encephalitis?

Nature is not only a great place to relax and a source of inspiration. It is there that we face great danger in the form of small blood-sucking parasites. They can be found everywhere: in the grass and on the leaves.

Ixodid ticks (Ixodidae) are carriers of the causative agent of tick-borne encephalitis, a disease that mainly affects nerve cells in the human body. These may be brain structures, peripheral innervation, or radicular nerve endings in the spinal cord. Science knows about 650 species of these arachnids. In our latitudes, two species pose the greatest danger: taiga and dog.

The encephalitis tick is a carrier of a dangerous and currently incurable viral disease

Every year, about 2.5 thousand Russians become infected with the encephalitis virus.

Taiga tick

A small spider from 4 to 6 mm, belonging to the order Arthropods. Most often it can be found in the forests of Siberia, the Urals, and the Far East. Due to the fact that over the last century there has been a sharp warming of the climate, the usual habitat of the taiga tick has expanded. Today it can increasingly be found in Belarus, the Baltic countries and south-eastern France. Taiga ticks are carriers of Lyme disease and tick-borne encephalitis.

In Russia, the taiga tick is one of two species that transmit the encephalitis virus

Dog tick

This type of tick is widespread in the European part of Russia, as well as in the countries of Central and Northern Europe. At the end of spring and beginning of summer there is a peak in the number of their bites. The dog tick is similar to a taiga representative of the family, and by external signs it is almost impossible to distinguish them from each other. Today it is quite often found in summer cottages and garden plots, at camp sites, and in places where dogs are kept. A humid microclimate and the presence of a host are the main conditions for survival.

Dog ticks pose a danger not only to animals, but also to people.

Contrary to popular belief, ticks very rarely fall from trees. More often they live in grass, soil and fallen leaves.

Ticks are the main carriers of viral encephalitis. But you cannot judge by the appearance of a tick whether it is infected or not. This can only be detected in laboratory conditions. The source of the disease is both the bloodsucker itself and its larvae. The cause of tick infection can be considered to be its previous activity on a sick animal.

How do Ixodid ticks reproduce?

The female tick lays about 15 thousand eggs after drinking blood. But not everyone will reach the adult stage; this largely depends on natural conditions. The end result is usually only a few dozen individuals. The clutch matures within a few weeks.

Incredibly, ixodid ticks feed only 3-4 times during their entire life, which lasts several years: in the larval stage, in the nymph stage, and a couple of times as adults.

The larva feeds once. Small warm-blooded animals become her victims, since it is difficult for her to get to the top. The feeding process can last for 2–3 days, and then the larva becomes a nymph (an adult without sexual maturity). The individual spends the winter in this state. With the onset of spring, the nymph is ready to hunt, and larger animals become its victims. In this state, it matures to the imago stage (adult sexually mature individual) within a year. Unlike females, sexually mature males need from 30 minutes to several hours of preliminary saturation to be able to mate.

Ticks are able to sense the proximity of a person or animal at a distance of 5–10 m. It is for this reason that parasites are found in large quantities on paths and roads.

Video: one tick - two diseases

Activity of encephalitis ticks in Russia

Long-term observations of ticks have formed a clear idea of ​​where insect habitats are mainly located. This allows doctors to calculate the density of bloodsucking insects and predict the scale of the problem in the current season.

The activity map of encephalitis ticks can also be useful for people who are far from science. This is a kind of practical guide that allows you to find out how active these parasites are in your region. Today, most of the territory of Russia is occupied by endemic (dangerous) zones for tick-borne encephalitis:

• Northwestern region (Leningrad region, Karelia, Arkhangelsk region);
• Central region (Tver, Yaroslavl, Vologda regions);
• Ural (Sverdlovsk, Perm regions);
• the southern part of Siberia (Krasnoyarsk Territory, Novosibirsk, Tomsk, Omsk, Irkutsk regions);
• Far East (Khabarovsk and Primorsky Territories).

Maps of the incidence of encephalitis are compiled on the basis of official data from the State Sanitary and Epidemiological Supervision of the Russian Federation on the maximum incidence for the current year.

The encephalitis tick activity map provides an idea of ​​the density of the blood-sucking tick in the country and marks the most dangerous regions

The first signs of an encephalitis tick bite in a person

Sometimes a tick bite, including encephalitis, is very difficult to notice right away, because the symptoms are similar to the malaise that is observed in many diseases. But still, a number of special characteristic features can be noted. The incubation period of the virus lasts at least 1–2 weeks, and only after this time the first signs begin to appear.

A tick bite becomes noticeable after some time due to characteristic signs

Symptoms of the initial stage of infection:

• high body temperature, which may alternate with chills;
• severe weakness, malaise;
• numbness and/or twitching in the neck, collarbone, shoulder blades or limbs;
• pain and stiffness of muscles in the cervicothoracic region, calves, arms, joints;
• severe headache and dizziness, because the viral infection primarily affects the brain and spinal cord;
• vision problems, loss of image sharpness, irritation from bright light;
• aversion to harsh sounds;
• problems in the gastrointestinal tract (gastrointestinal tract) - loss of appetite, nausea and vomiting.

The first signs of an encephalitis tick bite in a child or pregnant woman appear in the same way as in other victims.

The second phase of tick-borne encephalitis (after an 8-day remission) is accompanied by the following symptoms:

• fever;
• severe headache;
• muscle tone of the neck;
• convulsions;
• disturbance of consciousness;
• motor impairments.

Symptoms of borreliosis (Lyme disease)

Borreliosis occurs in 3 stages. Each one exhibits its own characteristic features:

• general stage of infection (4–5 weeks): general weakness;
• increased body temperature;
• muscle pain;
• the appearance of rounded redness around the bitten area;

  
  Rapidly enlarging round spots around the site of the tick bite are a characteristic sign of borreliosis

• hives;
• conjunctivitis;

Why is a tick bite not immediately felt?

The bite of any tick is not physically felt by humans. The arachnid completely imperceptibly injects an anesthetic substance into the skin of the victim with its proboscis, the so-called hypostome.

The tick digs into human skin using a proboscis with teeth called a hypostome.

The likelihood of contracting encephalitis from a tick bite

The risk of contracting an infection from a tick largely depends on geographic factors. In regions endemic for the disease (Urals, Siberia, Far East), the probability of infection with encephalitis is 20%. In the European part of Russia this figure is lower.

In the southern regions of our country, the risk of the disease is 0, since the tick in these places is a carrier of borreliosis and Crimean fever.

Additional signs

Unfortunately, it is not always possible to see a tick bite, since external signs may not be noticeable. Moreover, the virus, when it gets into a bite wound, develops quite slowly. In the first 7-10 days after infection, it may not cause any discomfort at all. However, in people with weakened immune systems, signs of infection may appear earlier, within 2-4 days after the bite.

The most common symptoms include:

• a sharp increase in temperature to 39°C (and sometimes higher), fever;
• body aches and flu-like illness;
• weakness;
• vomit;
• headaches and dizziness.

In this case, high temperature and fever usually coincide in time with the stage of active development of the virus. In total it can last up to 10 days. If the disease is limited to this, then we can say that it was a mild form of encephalitis, but the victim will receive very strong immunity to the virus. Although in some cases, fever can develop into a chronic disease.

It also happens that after the fever subsides, remission begins, which lasts about a week. It seems to a person that he is already completely healthy. But after a short period, the disease returns and the virus passes through the blood-brain barrier. Because of this, the nervous system is damaged, and encephalitis progresses to a severe (meningeal) stage. In this case, those internal organs in which the virus develops quite actively suffer. This stage of the disease is accompanied by photophobia and stiff neck. This means that the neck muscles become stiff, making it difficult for the patient to tilt their head to their chest. In some cases, brain tissue is affected and hallucinations occur.

It is very important to prevent this and consult a doctor in time. Diagnosis is all the more important because these symptoms themselves can be signs of completely different viral diseases or pathologies of the central nervous system. Therefore, the doctor, having examined the clinical picture, must make sure that there was a tick bite and collect information about which regions the patient visited (encephalitis ticks are not found everywhere). The tick itself can only be examined if the patient managed to remove it without damage. If this is possible, it is better to contact a doctor immediately after the bite so that they can also remove the parasite.

Only after a comprehensive examination is a diagnosis made and appropriate treatment prescribed.

First aid for a tick bite at home

The first step is to quickly remove the tick. The longer it sucks blood, the higher the concentration of infection (if present) in the human body.

At home, the tick can be removed with ordinary tweezers. It should be pulled out with twisting movements, carefully grasping it at the point of suction to the body (in close proximity to the proboscis), so as not to tear off part of it or crush it. If the bloodsucker is damaged, additional infection will occur if it is infected.

At home, ticks can be removed with ordinary tweezers.

Video: how to remove a tick

How to treat a bite site

After the tick is completely removed, the skin around the damaged area is treated with a disinfectant, for example:

• hydrogen peroxide or iodine;
• alcohol or alcohol-containing liquid (eau de toilette, lotion).

These substances should not be allowed to come into direct contact with the bite site. This can cause severe burns. The only approved remedy for treating open wounds is brilliant green.

What to do with a tick after removal

After removing a tick, you should never crush it (to avoid further infection) . Regardless of whether it is alive or dead, it is placed in a sealed container (bag, jar) and delivered to the laboratory for research within 2 days.

Is it possible to become infected with encephalitis without a tick bite?

Scientists have identified 2 mechanisms of infection:

• transmissible - infection occurs through the skin during a bite;
• nutritional - infection occurs by consuming milk from an infected animal.

What to do if a tick bites a pregnant woman

If a pregnant woman has been attacked by a tick, she should maintain composure and not panic. If possible, you should contact a medical facility to have it removed.

If this is not possible, then you can remove the tick yourself. This must be done with extreme caution so as not to crush the parasite or so that its head does not remain in the skin. Then proceed as follows:

1. Treat the bite site with any available antiseptic.
2. Place the extracted parasite in a resealable container with a small piece of cloth soaked in water.
3. Store in a cool place.
4. Deliver to the laboratory no later than 48 hours.
5. To rule out infection, get tested after 8-10 days.

When a diagnosis of encephalitis or borreliosis is made, treatment is necessary only under the supervision of a specialist. It is strictly forbidden to self-medicate, as this can cost the life of the pregnant woman and her unborn child.

Why is it dangerous?

Adult ticks are considered very dangerous to humans, as they can be carriers of dangerous diseases. Microtrauma occurs at the site of insect damage, and its secretions can provoke an allergic manifestation. Infection occurs during a bite, with some infections contained in the blood and others in the saliva of the parasite.

The diseases they carry can harm the nervous system and lead to irreversible consequences if help is not provided on time.

Important! Most infections that insects infect humans are treatable, but only in the early stages. Therefore, it is important to diagnose their presence as early as possible. If you miss the moment of development of the disease, this can be fraught with serious complications and even death.

Is it possible to become infected if it crawls through the body?

In order to suck blood, the arthropod clings to the skin so tightly that it cannot simply be shaken off. If the parasite did not have time to attach itself, it means that it did not have time to find a suitable zone for itself. The choice of the place to which to attach is important for the insect; therefore, a lot of time passes from the moment it lands on a person to the actual bite, which means that the parasite can be removed.

If the tick did not attach itself, but simply crawled across the body, then infection is possible if there is a fresh wound or crack in the skin. In addition, insect saliva can lead to the development of local allergies if the skin is sensitive to the substances contained in it.

Medical care for a tick bite

If you detect a tick bite, you should, if possible, quickly seek qualified medical help from a physician or infectious disease specialist. They will help you remove it at the emergency room. You can also call a clinic or ambulance station to find out the address to go to.

In a medical facility, they will competently remove the tick from the skin and tell you how to proceed next.

Diagnosis of infection after a tick bite

To identify a tick-borne infection, the victim undergoes a whole range of tests in the laboratory:

• ELISA (enzyme immunosorbent assay). Today this is the most common and most informative analysis. Shows whether antibodies to a virus or infection are present in the human body. The human body is characterized by 2 types of antibodies: IgG and IgM. They are detected when pathogenic microorganisms appear. If group M proteins are detected in the analysis, treatment begins immediately, because this indicates an infection has occurred.
• The Western blot method is used for the early detection of tick-borne encephalitis and borreliosis. It is similar to ELISA and is based on the study of venous blood.
• The immunofluorescent method is the most accessible analysis today. Due to its low cost, it is performed in almost all medical institutions.
• PCR (polymerase chain reaction method) is sometimes used to clarify the diagnosis. It helps to detect antibodies in urine and even in the skin.
• Cerebrospinal fluid analysis is used in rare cases when the results of other tests cannot make a diagnosis.

Personally, I have not had to deal with the problem of tick bites, but among my friends there are, of course, such. Two years ago, my friend’s 9-year-old daughter was bitten by a tick. The doctor carefully removed it with tweezers, treated the bite site with medical alcohol for disinfection, and gamma globulin was injected intramuscularly into the baby. Parents were advised to closely monitor the child’s condition, as well as bed rest. After 10 days, the child passed the tests, and everyone breathed a sigh of relief when they learned that everything was over and nothing terrible had happened.

Video: doctor’s recommendations for a tick bite

How long does it take for symptoms to appear?

Important. When bitten, ticks release a substance that has an analgesic effect, so it is impossible to immediately notice its attack. Only 3 hours after the bite a person may begin to feel chills, weakness or drowsiness, and a day later a feeling of mild nagging pain may occur.

If itching or fever occurs, this means that an allergic reaction to the insect’s saliva has begun.

Ticks can be sterile or infected. The former do not pose a particular danger to humans, since they are not carriers of any diseases. However, the bite of such individuals can be dangerous to humans, since the saliva can cause an allergic reaction. If the insect is infected, it can become a carrier of viral, microbial and other diseases such as borreliosis or tick-borne encephalitis.

What does the place where the parasite bit look like?

Obvious evidence of a bite is finding it on your body. If a person has been in places where parasites live, then an external examination should be carried out every hour and after coming home. The site of the insect bite looks like a small dark dot with reddened skin around it; it is rarely oval or with jagged edges.

In some cases, a small body may stick out from the reddened spot and look like a splinter. Sometimes it can be detected due to a local reaction such as itching or pain.

If you are bitten by a male, but you do not notice it, the situation may worsen. The fact is that after drinking blood, the male immediately disappears, leaving only the bite site and redness around it. One can only guess about the nature of this wound. If you do not find out the cause of its occurrence, you can find yourself in a dangerous situation and become infected with an unknown disease.

Attention. The female tick needs several days to get enough and fall off. It increases in size, so it is easy to notice on the skin. But in any case, a parasite bite can lead to infection under the skin.

Look at the parasites on the skin:

Complications of encephalitis and borreliosis

When bitten by an ixodid tick, serious complications can occur that are dangerous to human health and life . These include:

• failure in the neuropsychic system (neuroses and psychoses, nerve paralysis, dementia);
• pathologies of the heart (arrhythmia, angina pectoris);
• damage to sensory organs (loss of vision, hearing);
• the appearance of benign neoplasms at the site of the bite.

Undoubtedly, each of the listed diseases sharply reduces the standard of living of the victim, and even makes the person disabled. In severe cases, death can occur.

Measures to prevent tick-borne encephalitis

Vaccination is the only specific measure to prevent infection . Vaccinations against tick-borne encephalitis are indicated for persons who work in endemic areas permanently or travel there temporarily (business travelers, tourists, vacationers, gardeners and summer residents).

Vaccinations against tick-borne encephalitis are given in medical and preventive organizations, clinics, medical units, diagnostic centers, in first-aid posts of enterprises and educational institutions. Before visiting a potentially dangerous area, vaccination is carried out at least 1.5 months. This time is necessary to develop immunity to infection. If you were unable to get vaccinated against infection before the start of the season, you must follow a number of simple but very important rules when visiting potentially dangerous areas:

• give preference to light-colored clothing, as ticks will be more visible on it;
• clothing should be close to the body, with long sleeves and trousers, as well as with cuffs;
• tuck clothes into trousers;
• beware of tall grass and bushes, it is on them that parasites sit, do not walk along the edge of the path;
• be sure to wear a hat;
• treat clothes with repellent preparations;
• tuck trousers into high closed shoes.

Precautionary measures

1. To prevent ticks from getting on your body, you should be carefully equipped before going into the forest. It is advisable to wear clothes with long sleeves, thick elastic bands in the wrist area, and a collar that protects the neck. Protect your head with a hood or headgear. Tuck trousers into high shoes, covering the ankles.
2. It is recommended to choose light-colored clothing, then the brown tick will be more noticeable upon inspection.
3. Special repellents should be applied to the body to repel parasites. It is most convenient to use sprays, as well as cream and lotion. Collars are used for four-legged pets. Treating clothing and travel accessories with acaricidal agents - Brie-anti-mite, DEET, Taezhny, Garden - will increase the safety of your walk. These drugs kill the predator a few minutes after contact with clothing, so it does not have time to reach human skin.
4. On a personal plot, it is recommended to mow tall grass, in which arachnid predators are invisible. Treating plants with pesticides will significantly reduce the likelihood of encountering a parasite.
5. Vaccination against a dangerous virus gives an excellent result in the fight against encephalitis. The vaccination lasts for 3 years. It will prevent complications when an active virus enters the body.

Compliance with preventive measures significantly reduces the likelihood of an encephalitis tick bite.
If the parasite does stick, then the best option is to go to a medical facility. In most cases, people are not in any danger, but precautions will help maintain health in any situation. [youtube.player]

Encephalitis tick bite in dogs and cats

If a cat or dog is bitten by an infected tick, the animal develops piroplasmosis. The carrier is the dog tick. The incubation period after a bite lasts from 2 to 3 weeks. Most often, animals with weak immunity are susceptible to the disease; as a result of the development of the disease, they die.

As a result of a tick bite, an animal may develop piroplasmosis, a serious disease of the circulatory system.

Symptoms

Symptoms of the disease:

• increased body temperature;
• musculoskeletal disorders;
• convulsions;
• general lethargy;
• tachycardia.

The nervous system is most affected by the causative agent of the disease when bitten . The animal shows aggression, its behavior becomes unpredictable. A sure sign of the development of infection is the admixture of blood in the urine and further darkening of the urine.