Symptoms, treatment and effects of tick-borne encephalitis
- 1 General information
- 2 How does the virus manifest itself
- 3 Forms of pathology
- 4 Diagnostic methods
- 5 Medical events
- 6 Features of vaccination and prevention
- 7 Prognosis and complications
The virus spreads through the spinal cord and brain of children or adults, leading to severe intoxication and damage to the central nervous system. If untreated, severe forms of the disease cause paralysis, intellectual impairment, and death.
Tick-borne encephalitis is a focal disease that occurs in specific geographic areas. The causative agent of the disease is an RNA-virus (arbovirus), the carrier of which is an encephalitic ixodic tick that lives in Siberia, China, Mongolia, the Urals and other parts of Russia. The virus is characterized by microscopic size, which makes it possible to easily penetrate into the human body.
The frequency of diagnosis of encephalitis increases in spring and summer. Insects prefer to be in dense bushes, woodland with a high level of humidity. Parasites do not like sunlight and dry weather. During heavy rains and droughts, infection is practically not recorded.
Note! Among Russians 6,000 people fall ill every year.
There are 3 viral types:
- Far East – the most severe variety, difficult to treat. The probability of death is 40%.
- Siberian – less virulent.
- Western – accompanied by a mild illness. Mortality is 2%.
When a tick bites the virus immediately enters the bloodstream. The severity of the pathology depends on the victim’s immune response, the tick-borne variety and the number of bites. 6 out of 100 insects are carriers of the infection, from which only 4% are bitten. The tick bite leads to damage to the membranes of the spinal cord and brain, which causes the development of meningitis, encephalitis, meningoencephalitis.
It is also possible for a person to become infected with tick-borne encephalitis by drinking the milk of sick cows, goats. That is why doctors recommend boiling homemade milk. It is possible to infect with the fecal-oral method, when insect excrement gets on the affected skin.
The virus has low resistance to extreme temperatures, ultraviolet radiation and disinfectants. The infection dies after 2 minutes of boiling. Abnormal heat also destroys viral strains. Low temperatures prolong the life of the virus.
The duration of the incubation period
After a bite, a certain amount of viruses begin to replicate in the tissue tissue tissue, the rest – penetrates the bloodstream, spreading through the lymph nodes, vessels, nervous system. Typically, the incubation period of tick-borne encephalitis is 1-3 weeks, with infection by milk – 3-7 days.
A person infected with an encephalitic virus does not pose a threat to others, since it is not contagious.
Provide fulminant and prolonged form of the disease. With lightning-fast pathology, the first signs of tick-borne encephalitis appear a day after the bite. The latent period with a protracted form of the disease is a month.
How does the virus manifest itself
Tick-borne encephalitis is a viral infection, initially manifested by cold symptoms. After a tick bite, viral strains replicate in lymph nodes, tissue structures, and blood. Due to the penetration of the virus into the bloodstream, flu-like symptoms develop.
Symptoms of tick-borne encephalitis include:
- high body temperature, reaching 40 ° C;
- excruciating pain in the limbs, lower back;
- discomfort in the eyes;
- hearing loss, lethargy.
When an infectious agent penetrates the meninges and the brain, neurological disorders develop: a decrease in susceptibility, muscle dysfunction, problems with movement. Appears convulsive syndrome.
As the disease progresses, digestive disorders, disorders of the cardiovascular system join. Increased spleen, liver. The characteristic symptoms of intoxication are weakness of the upper and lower extremities, stiff neck, numbness of the skin of the face, neck.
In children, the disease proceeds rapidly. All symptoms appear brighter. An increase in body temperature is usually accompanied by convulsive seizures, vomiting.
Forms of pathology
The nature of the flow of encephalitis depends on the location of the pathogen in the human nervous system. Based on the localization, there are several forms of the disease.
It is diagnosed when viral strains penetrate into the bloodstream, but do not enter the brain membrane. Initially, signs of flu appear: feverish, fever, headache, nausea.
Neurological disorders are mild, there is a slight pain in the muscles, back. With successful therapy, a person feels weak for some time, lack of appetite, excessive sweating.
The most common type. A viral infection damages the dorsal and brain meninges. The disease is manifested by symptoms of meningitis: high body temperature, excruciating pain in the head, aggravated by movement, vomiting, photophobia, lethargy.
Rigidity of the occipital muscles develops, in which it is impossible to tilt the head to the chest, the muscles of the knee and ankle are stiffened. A person experiences pain even from a light touch.
Infection damages brain cells. The disorder of sleep, hallucinations, tremor of the extremities, disorientation in space is recorded. There are focal and diffuse meningoencephalitis.
The latter kind provokes attacks of epilepsy, impaired consciousness, difficulty breathing, muscle weakness. Focal infection is expressed in paresis, convulsive seizures.
Only the structures of the spinal cord are affected. A person becomes weak, his ability to move is deteriorating, his skin is numb. The patient cannot hold his head straight due to severe pain in the cervical region, shoulders. The muscular system gradually atrophies.
The roots and nerves of the peripheral division are damaged. This leads to pain in the whole body, tingling and pain in the hip, sciatic area.
The danger of this form lies in the appearance of Landry paralysis, when paralysis covers the lower limbs, gradually rising to the muscles of the face, the pharynx. A painful condition can cause respiratory blockage and death.
After the end of the latent period, body temperature rises, vomiting, dizziness, pain in the extremities appear. The feverish exacerbation is replaced by a normal condition lasting about 2 weeks.
After this period, encephalitis resumes. Pathological signs are increasing, accompanied by manifestations of meningeal and meningoencephalitic forms. The virus is treated the same way as febrile infection.
For a correct diagnosis, the doctor takes into account a set of several assessment criteria: clinical signs, instrumental studies and epidemiological information, including data on the presence of a bite and vaccination, seasonality.
The main diagnostic measures include:
- history taking, examination of the victim;
- virologic type blood test;
- puncture for the study of spinal biological material;
- virus testing to identify cells in physiological tissues.
Required to determine the amount of antibodies in the bloodstream. The presence of immunoglobulin M class indicates the occurrence of an acute infectious process, class G indicates the formation of protective reactions of the body. If both antibodies are detected simultaneously, a viral infection is diagnosed. All infected are examined for the presence of tick-borne borreliosis, as both diseases often progress.
It is recommended to bring a tick to the clinic, as the virus can be detected in an insect.
If bitten by a tick, you need to inspect the affected area. The damaged place will turn red, inflamed. As an emergency prevention measure, antiviral immunoglobulin must be injected, after which the necessary tests are taken.
If a parasite is found on the skin, you can try to pull it out with the help of a thread, forceps, or a special device sold in pharmacies. The best option would be to immediately seek medical help.
Initially it is required to hospitalize the patient, having identified the patient in the infectious disease ward. Bed rest is administered under the constant supervision of a physician. Encephalitis meningitis is treated only in a medical institution because it is impossible to predict how the body will react to the infection. Often a person is transferred to the intensive care unit, where they monitor the required indicators, daily taking blood tests.
Therapy of viral disease consists of a complex of therapeutic measures that require the use of the following drugs:
- infusions with glucose solutions, Sterofundin, Ringer;
- immunoglobulin, polyglobulin, neovir, interferon, laferon – etiotropic substances destroy the pathogens of encephalitis;
- glucocorticosteroids, which restore the state of the spinal cord and brain, eliminate puffiness;
- antipyretics, such as Infulgan, Paracetamol, excluding the use of Aspirin, as the acid increases the load on the liver;
- decongestants, furosemide, escinate, mannitol;
- anticonvulsant drugs – Sibazon, Oxybutyrate;
- agents that normalize blood circulation in the brain – Actovegin, Thiotriazolin, Dipyridamole;
- multivitamins, including vitamin B, – Milgamma, Neyrorubin.
A person needs rehabilitation therapy. During the recovery period, the patient is shown a massage, physiotherapy exercises, physiotherapy. Also needed classes with a psychotherapist, speech therapist.
Features of vaccination and prevention
Prevention of tick-borne encephalitis is the use of specific vaccines. Vaccination is a necessary preventive measure for people who work or live in forests. The risk of infection if they are bitten is very high.
The vaccine for vaccination includes an inactive virus that affects immune cells, stimulating them to form antibodies to infection and fight encephalitis. As a result, antibodies quickly absorb real viral agents.
The possibility of administering a vaccine is determined by the attending physician after assessing the state of human health. The vaccination is done three times, the second dose is administered 3 months after the first, the third dose – after a year after the second. Since the sensitive activity to the causative agent is maintained for 3 years, after this period of time it is necessary to revaccinate.
It is recommended to form a protective reaction of the organism before the seasonal activity of the virus. This requires the introduction of the first vaccine in the fall.
If a person falls into the peak of the incidence, he is given 2 emergency injections with an interval of 2 weeks. Such vaccination is allowed to be done once, subject to the introduction of the 3rd injection in 12 months.
Vaccination against tick-borne encephalitis is characterized by the presence of some contraindications. Injections are not administered with allergic reactions to the components of the drug. It is forbidden to make an injection during the course of any disease and taking medication. The procedure is also contraindicated in pregnancy, diabetes, tuberculosis, rheumatism, epilepsy, heart disease.
Among the non-specific preventive measures emit:
- wearing heavy clothing and hats when visiting forests;
- the use of repellents;
- body inspection upon returning home;
- if a tick is detected, it should be removed or the hospital should be asked for help;
- boiling homemade milk.
To prevent tick-borne encephalitis infection, it is recommended to combine vaccination with the observance of the usual preventive measures.
Prognosis and complications
The prognosis for recovery depends on the form of the disease. The febrile and meningeal form is easier to cure without leaving serious consequences. The remaining pathological forms are difficult, it takes years of treatment. Death rate is 30%.
Among the consequences and dangers of tick-borne encephalitis are a decrease in memory functions, systematic pain in the head, paralysis, and a decrease in muscle mass. The endocrine system is damaged, which is expressed in poor appetite, in women the cyclical nature of menstruation is lost. Brightly manifested neurological disorders, there is confusion, hallucinations.
The disease can provoke the development of irreversible phenomena in the nervous system, which causes malfunction of the vestibular apparatus. Patients lose the ability to move their heads, vomiting appears.
Tick-borne encephalitis is a serious disease affecting the brain. Pathology causes irreversible complications and death. To prevent the tick bite, you need to be vaccinated on time and follow the elementary rules of protection.
The following sources were used to prepare the article:
Gaivoronskaya A.G., Galitskaya M.G., Namazova-Baranova L.S. Etiology, clinical manifestations, treatment and prevention of tick-borne encephalitis // Journal of Pediatric Pharmacology – 2013.
Khafizova I. F., Fazylov V. Kh., Yakupov E. Z., Matveeva T. V., Khakimova A. R., Mullayanova R. F. Chronic form of tick-borne encephalitis: clinical features and diagnostics (literature review) // Journal Herald of Modern Clinical Medicine – 2013.