Experts told, what is really dangerous diagnosis of “encephalitis” and also explained in detail how to protect yourself from a tick bite.
The first description of the disease, is very reminiscent of KE can be found in the Church records of the Scandinavian countries of VIII century. TBE was first described as a distinct disease in Austria in 1931, writes the Chronicle.Info with reference to Мedinfo.
The pathogen was isolated in 1937 by Russian scientists under the leadership of L. A. Zilber. He was a member of the genus of flavivirus against which the world has still not developed any effective drug. Other cause flavivirus, e.g. yellow fever, Japanese encephalitis, Dengue and West Nile fever that are carried by mosquitoes and Russia are for the most part exotic/imported infections.
The tick-borne encephalitis virus neurotropic, that is, affects the nervous system. It suffers from the gray matter of the brain and its membranes (meningoencephalitis), and often, but not always, involves the spinal cord. Sick adults are heavier than children; one-third of survivors develop lifelong neurological consequences, often with impaired mental sphere and disability. However, it should be noted that the disease develops is not at all infected. Many people carry it without symptoms.
KE distributed from Eastern Europe to the Russian Far East and Northern Japan.
Viruses, as the name implies, the disease are ticks, namely Ixodes ricinus dog tick and the taiga tick Ixodes persulcatus. Dog tick carries the European subtype of TBE, whereas taiga is the source of more severe Siberian and far Eastern subtypes.
Annually in the world recorded 10,000 cases of TBE (who).
In nature, the main reservoir of infection, in addition to mites, are wild mammals, but, as the settlement of Siberia and the Far East and the displacement of animals from the forest areas, villages and suburbs, pokoritelya bloodsuckers become increasingly people.
The virus is transmitted to humans through the saliva of the tick within several minutes from the moment of suction, so a quick removal of the tick does not guarantee anything (just note that to remove a tick, however, it is necessary immediately, as soon as discovered, for the prevention of tick-borne borreliosis). In a few cases of human infection by drinking raw goat and cow milk from infected animals.
Ticks become active once the temperature is set at +6°C and above, so this disease is characterized by a clear seasonality. Activities, overwintered mites are selected from the forest floor and placed on the blades of grass or low bushes (usually not rising more than half a meter), and where waiting for pokoritelya. In this period the main thing for females of the tick to drink the blood, which is necessary for the development of numerous eggs.
Should be close to a warm-blooded animal, as it clings to the skin, wool, clothing and quietly creeps up until you find a secluded place — the person is usually under the clothing to cling to the body. The people in this place more often is back, armpits, groin, and wild animals, domashnih head, neck, groin.
Sated for 5 — 6 days with blood, the female falls from pokoritelya on the forest floor, there lays several thousand eggs and dies.
The virus actively replicated in most ticks at a temperature of 6-25°C and ambient humidity > 85%. In hot and dry climates the virus does not survive. Therefore, the peak incidence occurs in late may — early July.
Ticks themselves become infected, prikazivati to sick animals, and, in addition, transmit the virus to their offspring to progeny (i.e., through eggs). The tick can transfer the KE as in adulthood, and in the stages of larvae and nymphs.
In the case of canine tick infestation most often occurs from larvae and nymphs; in the forest much more, they malorazlichimyh in procerites, and in addition are very small, so they are difficult to detect on the body to suction.
As for the taiga tick in the transmission of infection much greater role played by adult ticks.
European TBE occurs usually in 2 phases:
The first flu-like phase develops within 1-2 weeks after the tick bite and lasts like the flu for about a week.
But after a few days it’s second phase with brain damage (from mild meningitis to severe encephalitis with spinal paralysis).
Far Eastern TBE begins acutely with fever, headache, intestinal disorders, which can quickly be followed by disturbance of sensation, coma, convulsions and paralysis. Death may occur in a week.
The diagnosis is confirmed by serological tests with detection in the blood of a patient with neurological symptoms antibodies to the virus (TBEV-IgM + typically detected TBEV-IgG). In the initial stages the virus can be detected using PCR. On brain MRI in about 20% of patients is defined by acute swelling of the basal ganglia, thalamus and trunk, but by itself the MRI diagnosis is not installed.
Nonspecific prevention involves measures taken to prevent the suction of the tick. Basic rules:
1) In tick season try not to visit without the need of place with highest density of mites (forest habitats with tall grass, bushes). Hiking trails should stay. For recreation, Parking or overnight camping in the woods preferable dry pine woods with sandy soil or areas devoid of herbaceous vegetation, where ticks are extremely rare.
2) Use insect repellents with DEET at least 25 — 30% (less concentrated not particularly effective) or means with acaricidal pyrethroids (permethrin and alpha-permethrin) type Gardeks extreme®, which paralyze the legs of the tick. There are very effective combined acaricide-repellent products containing DEET and PYRETHROID at the same time. Spray these funds not only on exposed areas of the body, but also on shoes and clothes. Especially thick treat places where the mite can move with the clothes on the body (ankle, waist).
3) Going into the woods, dress right! Wear light-colored clothes, which are easy to see bloodsucker. The so-called encefaliti khaki without acaricidal impregnation absolutely no good. Tuck pant legs into your socks, drop sleeves, hide your hair under a hat, sewn better under the hood. In recent years appeared in the sale and special costumes of the “Professional”, with sewn knitted obstacles-traps and fabric impregnated with synthetic pyrethroids, preserving the tick effect to 50 washings. These suits can be recommended to people working in the woods and hunters, mushroom pickers and other lovers of forest walks.
4) Regularly inspect your clothes and the clothes of the satellites in the woods. Remember that it is important to remove the tick from the clothes or skin until he sucked. For one third of cases the suction of the tick remains undetected, especially if the carriers had a larva (nymph).
5) Upon returning home, thoroughly inspect the body. Because some areas of the body inaccessible to self-should enlist the help of close inspection of the back and scalp.
6) Because the larval forms of ticks are very small, they can not be noticed on clothing. To avoid suction in the house should wash the clothes in hot water.
7) Upon detection of the stuck tick, it must be removed immediately. Remove the tick with tweezers can nail or thread, tying it around the head of the parasite. In practice, not deeply stuck tick is easy to remove just the nails, grasping it as close to the skin. The tick is removed raskazivali-vykruchivatsya movements. Avoid crushing the tick! The wound can be treated with any disinfectant (chlorhexidine, povidone iodine, alcohol, etc.). If the wound is left mouthparts of a tick, remove it as a splinter.
Most importantly: do not go to this clinic! The sooner a tick is removed the less likely to catch Lyme disease. Remote it is recommended to take the tick (alive) to the laboratory of your hospital for infectious diseases for study by PCR on TBE and Lyme borreliosis (however, such laboratories are only in major cities).
