Tick ​​habitats. Encephalitis tick: habitats

Types of ixodid ticks: which forests do they live in?

Where do ixodid ticks live?
Most often, ixodid ticks are found in dense areas of forest overgrown with shrubs, where the sun's rays do not reach. They especially love neglected forest clearings left in disarray by “black” lumberjacks.

The danger of tick attacks begins with the onset of above-zero temperatures, when the first thawed patches begin to appear, and continues until the end of September. In July their activity decreases slightly.

Forest ticks are small in size, reaching a length of 2-5 mm in a hungry state. Such arachnids belong to the subclass of arthropods and live almost all over the world, except Antarctica. The diversity of parasite species differs depending on the place of their life activity and the nature of their feeding.

There are other types of such parasites:

• gamasid, red beetles and argasid mites, which are also capable of consuming human and mammalian blood;
• dust mites (saprophytes), whose life is spent in living quarters with people, prefer to feed on dead particles of the epidermis;
• subcutaneous (Demodex) - live in the upper layer of the human epidermis and at the base of the hair follicles; they are tiny in size, so they can only be seen under a microscope.

Optimal living conditions where ticks are found:

• regions with high humidity, at least 80%;
• sun-warmed slopes with thick grass and shrubs up to 1 m high;
• The main habitat of ticks is: forest edges, clearings, ravines with dense grass;
• in the shade of deciduous trees there are thickets of ferns, among low young trees (aspen, hazel, etc.);
• Parasites most often live in coastal thickets near rivers, ponds, lakes and streams, where forest animals come to drink;
• soil surface with fallen leaves or mown grass.

Ticks in nature
The most unsuitable places for ticks to live: hills, areas without grass and plants, dry undergrowth in a pine forest, etc.

Among the family of ixodid parasites, there are some species that choose different habitats:

• Meadow ticks of the genus Dermacentor are carriers of many viral infections and can infect humans and even pets (pyroplasmosis in dogs). Distributed in areas of deciduous and mixed forests in Europe and Siberia, preferring clearings, forest edges, meadows and pastures, water meadows.
• The genus Hyalomma and its representatives prefer to settle in the steppe zone, living in the southern regions of Russia, Crimea, Bulgaria and on the Mediterranean coast, in Asian countries. They can spread hemorrhagic fever.
• Birch mites, belonging to the Haemaphysalis family, are moisture- and heat-loving parasites; their habitat is: Crimea, Transcaucasia and the Far East, Altai, the southern part of Western Siberia and Transbaikalia. They settle in birch-deciduous, coniferous-deciduous, aspen and birch forests. They can be carriers of encephalitis and rickettosis.
• The brown dog tick of the genus Rhipicephalus prefers coastal areas with high humidity: the Black Sea coast. The objects of its attack are often dogs, but the spread of dog ticks occurs very quickly due to their ability to reproduce in a person’s home or dog kennel, where they can establish entire colonies. They are carriers of Marseilles fever.

Where do ticks live and what climate do they like?

Ticks can adapt to various environmental conditions and can even survive at low temperatures. But there are conditions that promote rapid reproduction and comfortable life of arthropod parasites.

The carriers of encephalitis and borreliosis are most often taiga forest and European

mite. They prefer habitats where there is grass and shrubs, as well as areas of forest belt with dense vegetation. A safer place for animals and humans is where the grass is low and there is little vegetation. Ticks are not found on paved areas, wide trampled paths and clearings, but they love to wait for prey along paths.

Ticks are found in almost all types of forests, be it birch, spruce or mixed type. Only the coniferous environment is unfavorable for them. Encephalitis ticks live in almost all climatic zones of Russia, sometimes even found in harsh conditions beyond the Arctic Circle because they have learned to adapt to all environmental conditions.

Ticks feel most comfortable in areas with high levels of humidity.

In Russia, encephalitis ticks are found from Siberia to semi-deserts. Many cases of attacks have been recorded in the Moscow region and adjacent territories, in the Caucasus, in the Altai Republic, Volgograd, Kemerovo and Kirov regions. They are most common in the Far East, in the Central regions of Russia and in the Northwestern District.

The best weather for tick development is warm and humid, which is why the main peak of development occurs in spring and early summer

. Ticks cannot tolerate dry and hot weather; the scorching sun is destructive to them.

In which regions of Russia are there few ticks?

These bloodsucking creatures are least often found in the Northern regions of Russia, Siberia, the Urals, Magadan, Murmansk, Kamchatka and the Nenets Autonomous Okrug. But this does not mean at all that there are no ticks there and you can forget about precautions when visiting forests and parks.

Symptoms of the disease

Symptoms of European encephalitis at the first stage of the disease

Irritation at the site of the bite quickly passes, and the person forgets about the incident. But after 1-2 weeks he feels unwell and does not in any way connect this with the arthropod that bit him.

At the first stage, it is very difficult to distinguish between encephalitis infection and other diseases, of which there are a good dozen. And not all of them are contagious.

The main symptoms of European encephalitis in the first stage, lasting 2-4 days:

• muscle pain;
• lack of appetite;
• headache;
• fever;
• nausea, possibly with vomiting;
• general malaise.

At this stage, it is easy to confuse encephalitis even with regular flu and try to self-medicate. After 8 days (the period of complete recovery from the flu), remission occurs. The patient sincerely believes that it was the flu and forgets about the disease. If you're lucky, there will be no consequences of encephalitis.

But in 20-30% of infected people, after remission, the second stage of the disease follows with damage to the central nervous system:

• meningitis: severe headaches, tense neck muscles (similar to myositis), fever;
• encephalitis: impaired coordination of movements up to paralysis, sensitivity disorder, disturbances of consciousness;
• mixed form, which will “delight” with simultaneous signs of encephalitis and meningitis.

Far Eastern encephalitis develops more rapidly. It begins with a sudden increase in body temperature to 38-39°C. Severe headache and nausea appear. Sleep is disturbed. There is no remission stage. After 3-5 days, damage to the central nervous system develops.

It doesn’t matter what color the tick managed to dig into the body. In terms of transmission of infection, there is no difference between them

Moreover, in an infected area, any blood-sucking organism that parasitizes mammals can be dangerous. To prevent infection, it is necessary to follow safety measures and get vaccinated against encephalitis in advance.

How dangerous is the forest tick?

The insect bite itself is not dangerous to humans. Some types of ticks fall off almost immediately, so you may not even notice them. In addition to people, these bloodsucking creatures bite forest rodents and other animals. It is through intermediate hosts that they become infected with pathogens.

Table 1. Diseases transmitted through tick bites

People become infected with pathogens through intermediate hosts.

On a note! According to some data, the proportion of infected ticks is approximately 10-12%, so not every bite ends in hospitalization. In addition, a person may not get sick even from being infected by an infected individual.

How is the feeding process of ticks carried out and how does human infection occur?

• The sucked tick begins to secrete saliva into the resulting wound. The salivary glands of ticks are huge, occupying almost the entire body. Saliva performs various functions. The first portion of saliva hardens in air and forms the so-called “cement secretion”, which firmly adheres the proboscis to the skin.
• Liquid saliva, subsequently secreted, contains a lot of various biologically active substances. Some of them anesthetize the wound, others destroy the walls of blood vessels and surrounding tissues, and others suppress the hosts’ immune responses aimed at rejecting the parasite.
• The blood and particles of destroyed tissue entering the wound are diluted with saliva and absorbed by the tick.

How and why does infection occur?

tick map

As paradoxical as it may sound, the danger of infection with tick-borne encephalitis is an integral and natural property of our forests. The most important role in maintaining natural foci of infection belongs to small forest animals - voles, mice, shrews, squirrels and chipmunks. The animals themselves are susceptible to infection; the virus multiplies well in their bodies, but the disease proceeds without visible harmful consequences. In addition, the virus also multiplies in the body of its carrier, the tick.

In ticks infected with the tick-borne encephalitis virus, the pathogen is able to multiply in many tissues and organs and is very often present in the salivary glands. Having attached itself to the body of the host (including humans), the tick begins to secrete saliva into the resulting wound. The first portion of saliva hardens in air and forms the so-called “cement secretion”, which firmly adheres the proboscis to the skin. Together with this saliva, the virus enters the animal or human body, and if the dose of the virus is large enough, a disease may develop. As studies have shown, the above-mentioned “cement secretion” can contain up to half of the total amount of virus contained in the tick. Therefore, even if you remove the tick almost immediately after it has attached itself, you can still become infected, in this case the source of infection will be the “cement” remaining in the skin. It has also been proven that the infection is transmitted by the bite of males. A short-term and painless bite from a male may not be noticed, especially when the forest is full of mosquitoes and midges. Most likely, quite common cases of tick-borne encephalitis, when patients deny the tick bite, are associated precisely with an attack by males.

Where do virus-infected ticks come from in nature? The fact is that natural foci of tick-borne encephalitis existed long before the appearance of humans in Siberia. It is not known for sure whether the virus was originally associated only with ticks or only with vertebrates. However, in the process of evolution, the virus has adapted to exist in both organisms. Although the virus actively reproduces in wild forest animals, they do not exhibit pathological disorders characteristic of the human disease.

At the same time, those animals that do not encounter this pathogen in their natural environment (for example, house mice or some monkeys that are used as experimental animals in virological studies) get sick in exactly the same way as people.

So, infected wild forest animals, in which the virus is present in the bloodstream, serve as a source of infection for the ticks that feed on them. Having entered the parasite's intestines with the blood, the pathogen penetrates various organs and tissues, including the salivary glands, and begins to multiply there. When the mite sheds into the next phase of development, the pathogen persists. During the next blood sucking, the virus can enter the body of an uninfected animal and the whole chain of events is repeated again and again, ensuring a constant exchange of pathogens between ticks and their hosts.

Adult ticks pose a danger to humans.

What should I do if bitten by a tick?

If you find a parasite attached to your body, you first need to go to the hospital. The sooner you do this, the less likely you are to get tick-borne encephalitis. If it is not possible to see a doctor immediately after a bite, then you need to remove the embedded bloodsucker yourself.

It is strictly forbidden to squeeze out a tick, since if it ruptures, the infection will quickly penetrate the blood, and in this case the disease cannot be avoided. There are several ways to extract the parasite. The most effective is to take a thread and tie a knot as close to the bloodsucker’s proboscis as possible, then slowly pull the tick up with rotational movements. You should not do this abruptly, as the head may come off and remain under the skin. If this happens, it is necessary to treat the bite site with alcohol and remove the head with a sterile needle, like a splinter.

After the tick has been removed, the wound must be treated with alcohol or iodine. And put the parasite in a jar and take it to the laboratory for microscopic diagnostics. Important: he must be delivered to his destination alive so that specialists can examine him.

What does a tick eat?

Photo: Tick in the forest

Ticks also differ in their feeding methods.

Based on this feature, they can be divided into two groups:

• saprophages;
• predators.

Saprophages eat organic remains. That is why such mites are considered very useful for nature and humanity, since they make a certain contribution to the creation of humus. However, there are saprophagous mites that feed on plant sap. These are parasitic mites. This type of animal causes great harm to agriculture, as it can destroy grain crops.

There are mites that eat exfoliated particles of human skin - the epidermis. These mites are called dust mites or scabies. Barn mites are suitable for feeding on plant residues that decompose, incl. rotting flour and grain.

For subcutaneous mites, the ideal option is subcutaneous fat, which it takes from human hair follicles, and for ear mites, the fat from the ear canals. Predatory mites parasitize other animals and plants. Using its legs, a blood-sucking tick attaches itself to its victim, and then purposefully moves to the feeding site.

Encephalitis tick: life in pictures

Rice. 3. Photo of an encephalitis tick. Male (left) and female (right). They have a powerful shell and four pairs of legs.

Rice. 4 The female encephalitis tick lays eggs in May and June after it has fed on blood. Of the 1.5 - 2.5 thousand eggs laid, only a few individuals survive to adulthood.

Rice. 5. From the eggs laid by the female, after a few weeks, larvae the size of a poppy seed appear with a 3rd pair of limbs. Their prey is small animals and birds. Having sucked blood after 3 - 4 days, they leave the “breadwinners”. They molt in the forest floor and turn into nymphs. Nymphs reach 1.5 cm in length and already have four pairs of limbs. After spending the winter, the nymphs choose larger “breadwinners” for themselves. After a year, each nymph turns into either a female or a male. Almost all species of forest animals, livestock, and many species of birds that feed on the ground are sites of parasitism for encephalitis ticks.

During the entire development cycle, which lasts 3–5 years, ticks feed three times. Of all the eggs laid by the female, dozens of individuals survive and pose a threat to humans.

Rice. 6. Encephalitis tick bite. Ticks have huge salivary glands that span the length of their body. At the first moment of the bite, the secreted saliva firmly glues the proboscis to the skin. The liquid part of saliva anesthetizes the wound, destroys the vascular wall and suppresses the immune response of the host.

Rice. 7. Female encephalitis tick before and after sucking blood.

Rice. 8. Encephalitis tick after a bite (in the photo the female sucked blood). The ability to stretch the back of the body allows females to suck blood hundreds of times more than a hungry individual. Females attach themselves for 5 - 6 days. Males attach only for an hour. They spend the rest of their time searching for a female to mate with.

Rice. 9. The photo shows a female encephalitis tick. Ticks do not have eyes, but their sense of smell is very acute. They are able to detect the smell of animals and humans from up to 10 meters away.

Rice. 10. The photo shows a tick in an active waiting position - the front legs are extended and move from side to side. When the “breadwinner” approaches, the tick’s reaction is immediate. Their paws, equipped with suction cups, allow them to firmly cling to the victim.

Rice. 11. Encephalitis tick on humans. More often, the tick climbs up clothing and only then is found on the neck, head and shoulders. Ticks are very mobile!

Tick-borne encephalitis is registered strictly in the spring-summer period, which is associated with their maximum activity during this period.

Rice. 12. Encephalitis ticks on animals.

Rice. 13. Encephalitis ticks on animals.

Rice. 14. Encephalitis mites on birds.

Intestinal epithelial cells and salivary glands of ticks are the main sites of reproduction of tick-borne encephalitis viruses. Here they persist for many years and are released during the laying of eggs and are transmitted to some species of animals and birds through blood sucking, where they multiply and are transmitted to new ticks. By parasitizing the bodies of animals and birds, ticks infected with viruses are transported over vast distances.

Myth 3. A tick bite is painful

Unlike mosquitoes and other biting insects, tick bites are practically invisible. At the moment of the bite, the tick injects painkillers into the wound, and a person, as a rule, notices the bloodsucker by chance, running his hand over the area of ​​​​the skin where it has attached itself. Therefore, after walking in the forest or in the park, it is important to immediately examine your body, as well as your pets.

Ticks living in nature

What they eat depends on the lifestyle of ticks and their biological characteristics.

Ixodid ticks

There are many types of ixodid ticks. They are common in both tropical rainforests and desert areas. They feed on the blood of vertebrates: mammals, reptiles and birds.

For humans in our latitudes, the two most dangerous species are the European forest tick and the taiga tick.

The first is widespread in Europe (except for its northernmost part), North Africa and the European part of the Russian Federation. lives in the middle and southern zones of the taiga.

These two species are the main distributors of such dangerous diseases as viral tick-borne encephalitis, borreliosis (Lyme disease), and hemorrhagic fever. It is most likely to get Lyme disease due to tick bites in the Moscow region, Moscow, and Krasnodar region. In the Rostov and Volgograd regions, in the Caucasus region of Russia, there is a risk of contracting hemorrhagic fever. The situation with the spread of viral encephalitis is no better. This is the Northwestern District of the Russian Federation, Karelia, the Volga region, many regions of the Central District, and the entire Far East. In the easternmost part of the country, Vladivostok occupies a leading position.

It has been established that this species of arthropod is dangerous at almost all stages of its development. Nymphs and larvae look for a host after they are born. The larva waits for prey on the ground. As a rule, these are small rodents. The nymph prefers larger animals.

Demodex, or ironweed

Scientists have not established exactly how this subcutaneous mite spreads among people. There is an opinion that with close contact, common use of personal hygiene products and cosmetics, the disease passes from a sick person to a healthy one. It is worth noting that outwardly a carrier of demodex can be absolutely healthy.

Scabies mite

It is also called scabies itch. It is the cause of such an unpleasant disease as scabies. It spreads from a sick person to a healthy person after close physical contact (handshaking, skin-to-skin touching, intimacy). Animals do not get human scabies, but they can be carriers of it.

Can ticks live in the house?

It happens that after a walk, dogs or cats bring blood-sucking parasites into the house in their fur. Often the person himself quietly brings them into the house along with bouquets of forest flowers, berries or mushrooms. If you do not carefully inspect all your clothing after returning from the forest or park, you may not notice the parasite lurking on it.

How long can ticks live in an apartment?

Ticks brought in from the street will live in the house for no more than 9 months. They reproduce only in their usual environment. In an apartment where there is no plant litter, their eggs will not develop. Ticks cannot reproduce and live fully on a cat or dog.

Nevertheless, you should carefully examine yourself and your companions after each foray into nature, so as not to bring parasites into your apartment or private house.

Are there ticks in the pine forest?

When going on vacation to a pine forest, many are interested in whether there are ticks in the coniferous forest. It is difficult to encounter ticks on trees and foliage in a pine forest; this usually occurs when conditions are favorable for insects. If the forest has a high level of humidity, the area is well warmed by the sun, there are clearings and unharvested foliage, then such conditions for the growth and reproduction of parasites are ideal.

Therefore, before resting, you should take care of protection, use special means, clothes should be as closed as possible, and after a walk you should carefully examine the skin for the presence of bites.

Remember! Reproduction of ticks can occur in absolutely any forest, provided the climate is favorable. A wet area and deposits of dead wood are some of the conditions for the larvae to be found. Parasites are rarely found in dry pine forests, but in any case it is important to follow safety measures.

Dog tick

The Latin name of the species is Ixodes ricinus. The arthropod is widespread throughout the Eurasian continent. It can also be found in North America and North Africa. On the last two continents there is no encephalitis virus and there this type of tick is definitely not encephalitic. But it can give you other dangerous diseases.

The dog tick is an ordinary, arachnoid-like creature familiar to almost everyone. Dog breeders are more concerned about the piroplasmosis they spread than the encephalitis virus. The size of arthropods may vary depending on at what stage of development the tick decided to drink blood. The larvae and nymphs, differing from the imago only in size, begin to drink blood. A hungry nymph is 1.3-1.5 mm long. Adult male – 2.5 mm. Hungry adult female 4 mm long. Once it is saturated, it swells to 1.1 cm.

Dog tick

The body of a dog tick is shaped like an egg with a very sharp tip, and there is a proboscis on its head. The back is protected by a dark brown shield. In males, the shield completely covers the entire body. In females, larvae and nymphs, the shield is much smaller and protects only the front part of the back. The abdomen of a hungry female is gray below and black above.

Where are the most ticks?

They are found in areas with high levels of humidity, the most favorable place being mixed and deciduous forests. In Europe, parasites can easily be found in gardens, forests and city parks. Sometimes found in northern regions and highlands.

Forest ticks and dog ticks are often found in Russia (you can see the distribution halo above on the map). In the forest parks of the Far East and Siberia you can encounter the taiga parasite. The most dangerous place is Western Siberia and the Urals - more than 80% of cases of bites of such insects are recorded here. In Northern and Central Europe, as well as the European part of Russia, the encephalitis dog tick is widespread.

Previously, parasite bites and subsequent complications were occupational diseases, since they were infected by those whose work activities were related to the forest. It was noted that infection of rural and urban residents occurs in the same way.

Parasites choose areas with high humidity, so they are most often found in countries whose territories are rich in clearings, forest edges, low bushes and dense grass. European taiga and forest ticks pose a threat to human health. The latter species is often found in northern Europe, European Russia and North America. Taiga dangerous insects are common in areas of the southern and northern taiga.

These are carriers of particularly dangerous pathogens: hemorrhagic fever, Lyme disease and encephalitis. Borreliosis ticks are often found in the Krasnodar region, Moscow and the Moscow region. It is possible to become infected with hemorrhagic fever in the Caucasus, in the Volgograd and Rostov regions. The encephalitis tick was seen in the Far East, Volga region, Karelia, and Northwestern Russia. In the East, ticks are more common in Vladivostok.

Less common, but still found, are parasites along forest and park paths. When the temperature drops below 5 degrees, they burrow into moss or foliage. Insects are attracted to branches, debris, garden plots and parks rich in foliage. Similar places in large cities are not ignored either.

Where are ticks found: grass or trees?

Many people mistakenly think that the main habitat of ticks is on trees. This is not true: the favorite place of parasites is grass and fallen leaves. There favorable conditions for life and reproduction are created for them.

Ticks in the forest do not live on trees. Most often, parasites are found in grass, especially in parks where the grass is not regularly mowed, which is very convenient for them. By regularly cutting the grass and clearing the area of ​​leaves, the risk of encountering dangerous insects is quite low.

Adults usually sit on tall grass:

• adult specimens – grass above 1.5 m;
• nymphs - in grass at least a meter high;
• larvae – no higher than 30 cm.

But still, are there ticks on trees? No! Many people are mistaken in thinking that ticks are located on tree branches and, when the opportunity arises, jump onto a passing victim. Their habitat is tall grass, fallen leaves and dense thickets.

They show their activity at temperatures above 10 degrees. Most often, there is an increased risk of getting a bite in May and June; sometimes the parasites manifest themselves in April.

Knowing where ticks live and the period of parasite activity, you can significantly reduce the risk of getting a bite and developing complications.

Tick ​​behavior

An embedded tick in the photo The first active adult ticks appear in early or mid-April, when the sun begins to warm up and the first thawed patches form in the forest. The number of ticks increases rapidly, reaching a maximum by the beginning of the second ten days of May, and remains high until the middle or end of June, depending on the weather. Then it sharply decreases due to the extinction of ticks, whose reserve nutrients are depleted. However, single active parasites can be found until the end of September.

Ticks lie in wait for their prey, sitting on the ends of blades of grass, blades of grass, sticks and twigs sticking up.

When a potential victim approaches, ticks assume a posture of active anticipation: they extend their front legs and move them from side to side. On the front legs there are organs that perceive odors (Haller's organ). Thus, the tick determines the direction towards the source of the smell and prepares to attack the host.

Ticks are not particularly mobile; they can travel no more than ten meters on their own in their lifetime. A tick lying in wait for its prey climbs a blade of grass or a bush to a height of no more than half a meter and patiently waits for someone to pass by. If an animal or person moves in close proximity to a tick, its reaction will be immediate. With his front legs spread out, he frantically tries to grab his future owner. The legs are equipped with claws and suction cups, which allow the tick to grip securely. No wonder there is a saying: “He grabbed like a tick.”

With the help of hooks that are located at the very end of the front legs, the tick clings to everything that touches it. Ixodid ticks (European forest tick and taiga tick) never pounce and never fall (do not plan) on the victim from above from trees or tall bushes: ticks simply cling to their victim, who passes by and touches the blade of grass (stick) on which it sits mite.

Having settled on the animal, the tick chooses a place to feed. In most cases, this is the area of ​​the head and neck, where the animal cannot reach with its teeth and destroy the parasite. Then it plunges its mouth parts (the so-called proboscis) into the skin and, cutting through it, reaches the subcutaneous blood vessels, from where it sucks blood. The teeth on the proboscis, directed backwards, and the first portion of saliva, which quickly hardens and glues the oral organs to the skin, like cement, help it securely gain a foothold.

Female ticks feed for about 6 days, absorbing an incredible amount of blood, a well-fed female becomes the size of the phalanx of the little finger, her integument acquires a dirty gray color with a metallic tint, and her weight increases by more than a hundred times compared to the weight of a hungry individual.

Males attach themselves for a short time in order to replenish the supply of nutrients and water in the body; they are mainly busy searching for feeding females with whom they mate.

Tick ​​development cycle

In May-June, having engorged itself with blood, the female lays 1.5 - 2.5 thousand eggs, from which, a few weeks later, larvae hatch, they are no larger than a poppy seed and have only three pairs of legs.

The larvae attack small forest animals and birds, sucking blood for 3-4 days, then leave their hosts and go to the forest floor. There they molt, turning into the next phase of development - nymphs, which are larger and already have four pairs of limbs.

Having overwintered, the nymphs go out to “hunt” in the same way, but choose larger victims: squirrels, chipmunks, hares, hedgehogs. After a year, the engorged nymph turns into either a female or a male.

Thus, the development cycle of a tick lasts at least three years, and can drag on for four to five years. During this time, ticks feed only three times, and out of thousands of larvae, only a few dozen adult individuals emerge; the rest fail to survive.

Only adult females and males are dangerous to humans, while larvae and nymphs pose no threat.

Where do ticks hide and how do they attack?

Depending on the species and stage of development, parasites lie in wait for their victims on the ground, grass and bushes at a height of several centimeters to a meter. The larvae live on the ground, in deciduous and coniferous litter, crawl into animal burrows and parasitize small rodents and birds. Nymphs sit on the grass and cling to larger warm-blooded animals, and can also attack people. Adults lie in wait for their victims on the grass and bushes and attack mammals and humans.

When a tick chooses a place to hunt, it is guided by the following parameters: temperature, humidity, and availability of prey. Most often, these parasites are located on the grass along animal trails, in forest edges and clearings, pastures and vegetable gardens, in city parks and squares. Ticks do not climb trees, so there is no need to be afraid that a bloodsucker may fall or jump on your head from a birch or pine tree.

The pliers do not climb high. Their habitat is grass and small bushes.

On a note

There are mites that live on trees, such as spruce (Oligonychus ununguis) and pine (Oligonychus milleri) spider mites. They are completely safe for humans and are plant parasites. In addition to spruces and pines, they also infect various conifers, thujas and junipers. The web with which these parasites weave around plant shoots serves as protection for the colony and, when picked up by the wind, helps the pest spread. To combat spider mites, summer residents spray trees with special acaricidal compounds.

Having found a convenient place, the parasite freezes, extending its front pair of legs with claws. When the smell of prey reaches him, he turns in its direction and makes oscillatory movements with his front pair of legs until contact occurs.

This is interesting

Haller's organs are the main olfactory receptors of mites. With their help, the parasite senses the victim by thermal radiation, smell and carbon dioxide released.

If the owner continues to be felt nearby, but contact has not occurred, the bloodsucker can descend and cover a distance of 5-10 meters to the selected prey.

The parasite clings to the victim's skin, fur, feathers or clothing using hooks, spines and bristles covering its legs. These adaptations help it hold tightly and crawl over its prey in search of a place to bite. The bloodsucker looks for a place with thin skin and closely spaced blood vessels - for example, the armpits, ears and the area behind them, the groin. He can crawl over the victim's body in these searches for several tens of minutes.

Having found a convenient place, the tick cuts the skin with chelicerae and inserts the proboscis-hypostome into the resulting incision. The parasite's saliva contains anesthetic substances, thanks to which the victim does not feel the bite, and anticoagulants, which prevent blood clotting and ensure continuous nutrition of the parasite.

The tick immerses its proboscis along with its head under the skin, injecting an anesthetic substance, so a person may not notice for a long time that there is a parasite on it.

The tick's mouthparts are completely immersed in the wound and, thanks to their special structure, act as an anchor, ensuring a strong anchorage in the skin. The feeding process can last from several hours to a week until the tick is completely satisfied.

Why are there more and more ticks?

It turns out it's not the mites at all. They themselves are quite harmless. They were slandered. Ticks are carriers of infection; they are victims, not criminals. They are infected by small forest animals. If our country is completely enslaved by ticks, the number of cases may not increase, but even decrease. But if mice or hedgehogs are enslaved, epidemics are inevitable. In recent years, there has been an increase not in ticks, but... in mice. There are many reasons for this. For example, the amount of household waste in parks and forested areas attracts small rodents. Climate change - the warmer the winter, the higher the likelihood that both ticks and small animals will survive the winter well. Logically, after the frosts that tormented us this winter, there should be less of both. But if you ask a doctor from a vaccination center or an insurer, or a representative of a pharmaceutical company about the “tick-borne” situation, they will, of course, answer you with horror in their eyes: there are more and more ticks every year, MORE!

What are the forms of encephalitis? Symptoms of the febrile form

If, for example, two people become infected with tick-borne encephalitis, then even their symptoms may differ. Of course, the general symptoms of the virus are the same as for all infections of this type, but then, as they say, there is more. In addition, animals and humans have different signs of the disease.

The following forms of encephalitis exist:

• Feverish (mildest);
• Meningeal (the most common, slightly more severe than febrile);
• Meningoencephalitic (moderate or severe form, not very common);
• Poliomyelitis (severe, even more rare);
• Polyradiculoneuritic (not often seen).

In general, symptoms also vary depending on how strong the immune system is, as well as on the amount of virus introduced into the body.

The incubation period ranges from 7 to 14 days. The first symptoms of encephalitis, inherent in any viral infection, appear after 2-4 days if the body is weakened, and after 7-10 days if the immune system is normal.

Symptoms of any of the forms manifest themselves as follows:

• Fever and temperature from 38 to 40 degrees (possible duration from 5 to 10 days);
• Headache;
• Weakness, lethargy;
• The body aches;
• Vomiting and nausea.

The febrile form works like this: the above symptoms appear, and if after 5-10 days the disease ends with fever, then the person can fully recover and gain lasting immunity to the disease. Sometimes it happens that the febrile form develops into a chronic one. This form means that the person will occasionally experience increased symptoms of NS damage. But if everything ended at this stage, it means that the disease did not progress into the breeding season.

There is such a dangerous point here: the febrile form can go to the next stage, but at the same time an improvement in the person’s condition will be observed. This is the so-called remission. But it's not that simple. Improvement usually lasts 7-10 days, after which the virus penetrates the brain barrier, affecting the nervous system and transforming into one of the forms, most often meningeal. At this stage, internal organs are damaged; this is the period of reproduction. In this case, the flow of the form will be easier than if it flowed in its original form. In this case, the febrile stage is a kind of “vaccine”.

Reproduction

The breeding season for ticks begins in early spring (April-May), as soon as the air temperature reaches above zero. Fertilization of the female can take place both on the host and on the ground. After fertilizing several individuals at once, the male dies. The female, having had enough to eat, falls to the ground, looks for a secluded place under the leaves or in soil crevices and, after 6-40 days, lays eggs. The number of eggs reaches 2000-3000 pieces. After oviposition, the female dies.

An interesting fact is that procreation can take place without the participation of a male individual, in which case all offspring will be female. Thanks to this fact, the tick population not only does not die out, but increases every year.

Important! The high risk of tick attack occurs during the period of activity and reproduction - in May-June, as well as in August-September, in warm weather

Statistics of encephalitis infection in Russia

In 2021, 32 people died from a tick bite followed by encephalitis (according to Rospotrebnadzor). In 2021, there were 510,000 visits from people bitten by ticks to seek medical attention. This figure is higher than last year and generally exceeds the annual average.

Every year from 2010 to 2021, from 29 to 50 deaths from viral tick-borne encephalitis were recorded. In 2021, 29 deaths were recorded, including one child.

The main causes of complications and death from encephalitis are neglect of vaccination and late consultation with a doctor. The sanitary treatment areas increase every year, but the number of victims does not decrease.

In the Moscow region from 2021 to 2021, 41 cases of tick-borne encephalitis were identified, all of them certified by the laboratory. There were also 14 cases where the virus was accidentally brought from other regions of Russia. As statistics show, vacationers mainly catch the infection when they go on vacation in the region to nature. Since 2003, cases of a local nature began to be recorded; for 2015-2017, this figure reached 113 registered cases out of 2873 available. For 2021, the percentage of people infected with encephalitis, namely 62%, occurred in the capital of the Russian Federation - Moscow and the region.

According to data for all past years, a greater number of infected people were noted in the Republic of Tyva. The table shows statistics with the highest rates.

Diseases carried by the encephalitis tick

Encephalitis tick is an insect infected with the encephalitis virus. When an infected tick comes into contact with human skin, it transmits the virus. What follows are consequences that no one can predict. It all depends on the treatment and the course of the disease.

Where does the dangerous tick live? Everywhere, including the coldest and hottest continents of the globe. What does an encephalitis tick look like? It is impossible to tell by the appearance of a tick whether it carries the encephalitis virus or not. Only a laboratory assistant can answer this question by examining the insect for the presence of the virus.

A man was bitten by a tick, it was taken out of the human body and sent to the laboratory. At this time, you cannot wait for results. You need to act immediately. Whether the tick is infected with encephalitis or not, preventive measures must be taken, and without delay.

Places of encephalitis tick activity in Russia

How does a virus introduced by an encephalitis tick into the human body develop? There are 3 options for the development of the disease.

What does an encephalitic infected patient look like if he has the mildest form of the disease? The same as always. Everything is within acceptable limits. An encephalitis tick bites a person, then the insect is removed from the body. No symptoms appear. Then the patient donates his blood for testing. Antibodies are detected in it: the body has independently coped with the disease, developing encephalitis immunity.

The consequences of getting an encephalitis tick on the skin are not always so successful.

The first symptoms of encephalitis:

• acute headache;
• photophobia;
• redness of the upper half of the body;
• dry skin;
• decreased tone of the neck muscles;
• intoxication and fever.

Symptoms after an encephalitis tick bite
In the most severe cases, the following are observed: epileptic seizures, confusion, hallucinations, paralysis, and this is not all that the encephalitis tick is dangerous for. The worst outcome, observed in 20-25% of cases, is death. This is considered to be a good indicator, since there are periods during which this figure increases significantly.

The situation is complicated by the fact that a layer of secondary infections is added to the activity of the virus. And all this happens because proper prevention was not carried out. You cannot put off until tomorrow everything related to ticks. The faster measures are taken, the greater the chances of a speedy recovery. A tick with encephalitis is much more dangerous than an uninformed person might imagine.

Are there parasites in the city?

Ticks in the city are not a rare phenomenon, it all depends on the territory and the number of plantings. There is a high probability of encountering parasites in a city where there are recreational areas and parks populated with a lot of greenery. The ability of dangerous insects to get into different places is still unknown, but statistics have shown that insects are increasingly appearing in places where they were not there before.

If there is a high risk of ticks, control services must treat such areas with special means. At the same time, it is not always possible to completely get rid of insects, so when traveling to the city that seems safest at first glance, you should be careful and take safety measures. The danger lies not in the bite itself, but in the pathogens that they can transmit from an infected animal.

In large cities, according to statistics, ticks with an encephalitis pathogen are practically not found.

Do not forget about precautionary measures, especially for areas with abundant vegetation, as well as areas adjacent to forests, summer cottages and livestock fields. You can often find parasites in small towns, villages or urban villages, where the population does not exceed 100 thousand people.

In such urban areas, blood-sucking insects are found along sidewalks; the risk of a bite in this case is as high as when you are in an open field. In such areas there is no special fight against ticks, since cities have small budgets, which are not enough to include measures to combat dangerous insects.

In cities with a population of over 500 thousand people, hazardous areas are treated with anti-tick agents during peak times of the year. Cases of bites are increasingly being recorded in big cities, in the suburbs and outskirts, and fishermen and summer residents are also suffering.