Tick-borne encephalitis: the path of infection, treatment
About tick-borne encephalitis have heard, probably all. With the approach of summer can often be found TV and radio programs about the disease, articles in newspapers and magazines. What is that tick-borne encephalitis (TBE), than it is dangerous and how to protect yourself from it?
Carriers of the disease - ticks. Unfortunately, they can be found in almost all the forests of Eurasia. And, although the carriers of the virus are not all the mites, but only 2 - 15% of them, the probability of contracting in the case of a bite is still quite large.
Ticks are very fond of mixed forests with denseunderbrush, bushes, tall grass. They prefer damp places. But direct sunlight and dry air is not to their liking. In very hot weather or during heavy rain, these parasites are inactive and almost no attack.
In different areas the activity of ticksdifferent. The most dangerous are parasites that live in the Far East and Eastern Siberia. Compared with these regions in the European part of Russia the situation is calmer, but neglect the precautions when leaving the nature should not be.
It should be borne in mind that "for ticks" completelynot necessarily to go far into the woods. This insect is quite possible to bring home with a bouquet of flowers, gathered herbs. Even with mushrooms, bought on the market.
Are active carriers of tick-borne encephalitisspring - summer. Asian mites exhibit maximum activity in the first half of the summer, usually in May and June. But their European counterparts are active twice a year. They are somewhat reduce its activity in July to re-enter the hunt in August and September.
But disease caused European ticksIt takes place in a lighter form. According to statistics, in the Far East, tick-borne encephalitis in 20 - 40% of cases leads to death. For the European part of Russia, the figure is 1 - 3%.
Ticks infected with the human in the process of bloodsucking. And the female sucks the blood for a long time, usually several days. At the same time it increases the weight of about a hundred times. But males suck just a few hours, and suction can sometimes be overlooked, although infected with encephalitis can be as early as the first minute after suction an infected tick.
Forms and stages of tick-borne encephalitis
Most often, the disease manifests itself in the 10 - 12th day of the disease, although the incubation period may be from 7 to 21 days.
Tick-borne encephalitis can be subdivided into several clinical forms. Any of them starts, usually acute, that is suddenly. The first symptoms are very similar to those observed with the flu:
- rapid rise in temperature to 38 - 39 °
- pain in the whole body
- weakness, fatigue
- loss of appetite
- nausea, sometimes vomiting
Tick-borne encephalitis occurs, usually in several stages:
- Stage 1. At this stage, the virus replicates only in the blood, may not penetrate into the nervous system. No symptoms other than those listed above may not be observed. Fever lasts for several days - up to about 10. The most lightweight, feverish form of the disease at this stage is the first stage zavershaetsya.Posle possible drop in temperature for a few days. Meanwhile, the virus overcomes system barriers between the nervous and circulatory systems of the body, called the blood-brain barrier and into the brain. Stage 2 begins.
- 2 stage of tick-borne encephalitis. The virus affects the brain membrane. The patient experiences a severe headache, there is photophobia, vomiting. There is a stiff neck, that is, their stress is that the patient can not bring your chin to your chest. At this stage ends with meningeal, the most common form of the disease.
- Stage 3 is present in forms that are acceptedcalled focal. At this stage, the virus infects not only the shell, but the brain cells themselves. Symptoms depend here on in which part of the brain lesions are located and what size they have reached.
For meningoencephalitic form encephalitis is characterized by impaired consciousness, the emergence of seizures, mental disorders, movement disorders (paresis and paralysis).
When poliomieliticheskoy form of the diseasedamaged nerve cells in the cervical spinal cord. Observed sluggish (ie complete absence of movement) paralysis of muscles of the neck and hands, which often lead to disability.
It is the latter two forms are the mosthazardous, with a probability of death. Even when they leave the patient recovery "in memory" headaches, paralysis and other neurological problems.
Differential diagnosis of tick-borne encephalitis
Diagnosis of the disease is extremelydifficult. In one clinical symptoms to determine the tick-borne encephalitis is not possible - in fact, these symptoms are typical for almost any infectious disease.
Suspected encephalitis can be based onthat the patient is in the countryside, in the woods. On the idea of QE, of course, is to bring the fact that the patient has been bitten by a tick. But, as we remember, the male mite can infect humans and stay at this unnoticed.
In order to confirm the presence of tick-borne encephalitis, require special analyzes on:
- Immunoglobulin M (IgM). The presence of immunoglobulin in the blood indicates that the virus of TBE have recently entered the body.
- Immunoglobulin G (IgG). These antibodies appear later in the blood than M, and stored after recovery throughout life. They provide life-long immunity to the pathogen of the disease. It is for the production of IgG is a vaccination against tick-borne encephalitis.
The presence of both antibodies speaks about infectionhuman TBE virus. Unless IgG detected in the blood - thus, a person, or sick for a long time or has been vaccinated or had already suffered the disease.
- Polymerase chain reaction (PCR) of blood and cerebrospinal fluid (CSF) in the tick-borne encephalitis - allows you to detect the virus, the causative agent of the disease.
All patients were examined at the same time TBE tick-borne Lyme disease, since it is not possible human infection once both infections at once.
Treatment of tick-borne encephalitis
Treatment is usually limited primarily symptomatic therapy. The patient is required to be appointed strict bed rest.
Sometimes, to neutralize the virus usedprotivokleschevoy immunoglobulin (a drug that contains the IgG antibodies to the causative agent of the disease), but the feasibility of such treatment delivered is currently being questioned. European medicine has renounced the use of immunoglobulin G for the treatment of tick-borne encephalitis.
In the treatment of TBE vitamins may be used. For example, ascorbic acid (vitamin C), which enhances immunity and improves liver function to neutralize the toxic substances. The day the patient is administered 300 to 1000 mg of ascorbic acid.
In addition to ascorbic acid, the patient is recommended vitamins of group B.
From one person to another tick-borne encephalitis is not transmitted, so the isolation of the patient in this case is not required.
Prevention of tick-borne encephalitis
I. Vaccination against tick-borne encephalitis
If you live in an area where the probability of meetingwith encephalitic tick is quite high, or plan a trip to this area, you should be warned beforehand about the vaccination against tick-borne encephalitis. Vaccinate, you can at any time of the year. But always keep in mind that a possible meeting with the tick should be held not earlier than fourteen days after the second injection of the vaccine.
It must be remembered that the immunity is finally formed only 45 days after the second vaccination. If vaccination against tick-borne encephalitis made by the emergency scheme, this period is reduced to 28 days.
Vaccines against tick-borne encephalitis
Today in Russia are used asimported and Russian vaccine. They are about the same in composition. Their production technology is also very close. In all cases, in chicken embryos grown viruses - pathogens, then they are rendered harmless.
All vaccines not live pathogendisease, so infected with encephalitis after administration of the vaccine is not possible. The body is introduced only antigen of the virus particle. This antigen is the human immune system starts to produce antibodies - immunoglobulins. When the body gets the actual virus - the causative agent of TBE already present in the blood immunoglobulins quickly neutralize it.
All vaccines are active against both Europeanencephalitis and against Asian types. Their effectiveness is quite large. According to various sources, after three administration of the vaccine completely protected from the virus are between 90 and 98% of vaccinees.
What are the contraindications a vaccine against tick-borne encephalitis?
For imported vaccines are very few contraindications:
- allergies to egg protein;
- any acute infectious disease (vaccination may be carried out only two weeks after recovery);
- up to 1 year.
For the Russian vaccine against tick-borne encephalitis list of contraindications is much broader:
- The presence of food allergies (especially on egg white);
- Allergy to medicinal substances;
- Systemic connective tissue diseases;
- Complication or too strong reaction (swelling and redness with a diameter greater than 8 cm, temperature above 40 °)
- After the first administration of the vaccine;
- bronchial asthma;
- Frequent epileptic seizures;
- Blood diseases;
- Exacerbation of chronic kidney and liver diseases;
- Cardiovascular insufficiency of II or III degree;
- A stroke or myocardial infarction that was once suffered;
- Endocrine disorders (thyrotoxicosis, diabetes, etc.);
- Malignant neoplasms;
- Pregnancy (vaccination possible two weeks after delivery);
- Any acute infectious diseases (the vaccine is administered one month after recovery);
- Viral hepatitis and meningococcal infection (the vaccine is used six months after recovery);
- Age up to 1 year (for vaccine EnceVir - age up to 3 years).
Can I be vaccinated against tick-borne encephalitis in a pregnant or lactating woman?
The fact is that at the moment there are noReliable knowledge of the effects of vaccines on the fetus. It is also unknown whether the components of the vaccine are allocated to the mother's milk. Therefore, pregnant and lactating women are vaccinated only in case of emergency. Preliminary should be weighed all the pros and cons, assess the real risk of infection of a woman with tick-borne encephalitis.
II. Closed clothing, regular inspections
Going to the forest or mountains, put on a light garment with long sleeves, preferably with a hood. If there is no hood, be sure to hide the hair under any headwear. Pull the trousers in your socks.
Absolutely not suitable for hiking in the forest clothes made of velveteen, wool and other uneven cloth, since it is difficult to notice the tick on it.
Every quarter of an hour, inspect clothing andDiscard all the insects on it. Returning from the forest, carry out a thorough examination, paying special attention to the groin area, armpits, ears, neck - mites often suck in exactly these places.
Clothes on return from the forest should be washed in hot water.
III. Use of repellents
Means that repel ticks (Off, Extreme !, GALL-RET, DETA-VOKKO, DEFI-Taiga, Biban, and others) are now sold in almost all stores.
Apply them to the exposed areas of the skin, as well as to clothes. It is recommended to apply repellent around the waist, neck, ankles, knees, on the sleeves.
Repellents have a deterrent effect onCarriers of tick-borne encephalitis. Having discovered such a substance, the parasite creeps in the opposite direction from it. The effect of repellents applied to clothing persists from several hours to five days.
There are also more dangerous for ticks means -Acaricide ("Refatamide taiga", "Pretex", "Picnic-Anti-cellulite", "Gardex-Anti-cellulite", etc.) and insecticide-repellent agents (Medilis-comfort, Kleshch-kaput, Kra-Rep) Etc.) These funds, deposited on clothes, retain their ability to destroy parasites for up to two weeks.
Because of the strong toxicity, insecticidally-repellent and acaricidal agents are categorically forbidden to be applied to the skin. Do not also use them to protect children.
For children, there are special repellents containing less toxic components: "Off-Child", "Efkalat", "Biban-gel", etc.
If you find a tick
If you find a sucking mite on the body,Remove it with a manicure tweezers. If there were no tweezers at hand, wind the head of the parasite with a thread as close to the proboscis as possible and gently pull it out.
Attention: Taking out the tick, try not to make sudden movements. Smoothly shaking and twisting, try to gently pull it out without crushing (when crushing a tick, a bite of tick-borne encephalitis can be released into the bloodstream). The wound should be treated with alcohol, iodine solution, chlorhexidine or other disinfectant after removing the mite.
If it so happened that the head of the tick remained in theBody (you will see a black dot at the same time), treat this area with a disinfectant solution, take the needle and remove the head as the splinter normally removes.
To remove the tick, you can go to a medical facility. However, one must bear in mind that the prompt removal of the tick reduces the probability of infection of the bitten.
If a person has been bitten by an encephalitic mite, emergency preventive measures are used.
Measures of emergency prevention
Introduction of anti-malignant immunoglobulin. Obtain this drug from the blood of donors that have been vaccinated from CE.
Antifungal immunoglobulin is injected ungraftedPeople. Sometimes it is injected and vaccinated - if there were several ticks, or if there was a repeated infection with tick-borne encephalitis virus a month and a half after the first.
The expediency of introducing anti-maltreatmentImmunoglobulin in many doctors is a big doubt today. Studies have shown that the administration of immunoglobulin helps to prevent the disease in a maximum of 60% of cases.
In addition, with the use of immunoglobulin, the risk of side effects is high enough.
Caution: In no case should you administer this medication yourself! The risk of such treatment can far outweigh the possible benefits.
Yodantipirin is an antiviral drug,Possessing immunostimulating action. It was approved for use in 1996. It is used as a means for emergency prevention of tick-borne encephalitis in adults and adolescents from the age of 14 years.
According to research, in its effectivenessIodantipyrine is superior to anti-malignant immunoglobulin. It can be freely purchased at a pharmacy and taken with you outside the city. Thus, you can immediately take Yodantipyrine, if, despite all precautions, you are still attacked by a tick.
The drug is taken in the first two days afterDetection of the parasite of 3 tablets three times a day, then two more days for 2 tablets, also three times a day. Finally, the next five days take one tablet a day.
Caution: Iodantipirin is contraindicated in cases of hypersensitivity to iodine preparations.
Pediatric anaferon can also help in thisThe case. In the case of a tick bite, children under 12 years of age are given an anaferon tablet three times a day. A child over 12 years old - two tablets. Prophylactic intake of anaferon is discontinued three weeks after the mite is detected on the body of the child.
It is important to remember that emergency measures are not effective enough compared to vaccinations against tick-borne encephalitis and do not protect against other diseases that are carried by ticks.</ P>