Symptoms of tick-borne viral encephalitis

The incubation period for tick-borne encephalitis is from 7 to 21 days, on average 10-14 days. The disease begins acutely, usually with a rise in body temperature to 39-40 ° C, severe headache, chills, fever, weakness, nausea and vomiting. From the first day of the disease, facial hyperemia, injection of scleral vessels, photophobia, pain in the eyeballs, often in the limbs and lower back are noted. The child is inhibited, drowsy. Meningeal symptoms quickly appear: rigidity of the occipital muscles, positive Kernig and Brudzinsky symptoms. On the 2nd-3rd day of the disease, encephalitic syndrome appears with impaired consciousness from mild stupor to deep cerebral coma, generalized seizures up to the development of epileptic status, sometimes there are signs of psychomotor agitation with delirium and hallucinations. Hand tremors, twitching of facial and limb muscles are often observed. Muscle tone is reduced, reflexes are depressed.

Against the background of the clinical picture of diffuse encephalitis, some children may develop signs of focality. Particularly characteristic of tick-borne encephalitis is damage to the lower parts of the brainstem with the involvement of the nuclei of the IX, X, XI and XII pairs of cranial nerves and the appearance of bulbar disorders: aphonia, swallowing disorders, paresis of the soft palate, hypersalivation with subsequent disturbance of the respiratory rhythm and a drop in cardiovascular tone. With damage to the white matter of the brain, spastic paresis of the limbs may appear. Hemiparesis is often accompanied by central paresis of the facial and hypoglossal nerves on the affected side.

Focality can also manifest itself in various hyperkinesis events that arise as a result of irritation of the white matter of one of the hemispheres of the brain by rapidly forming scar tissue.

With the involvement of the gray matter of the spinal cord in the pathological process, the clinical picture of the disease reveals poliomyelitis syndrome with flaccid paralysis: paresis of the muscles of the neck, limbs and trunk.

Cerebrospinal fluid in tick-borne encephalitis flows under increased pressure, is transparent, with moderate lymphocytosis. The amount of protein is initially normal, and during the recovery period it is slightly increased.

In the blood at the height of intoxication, moderate leukocytosis with a shift to the left to band neutrophils, increased ESR are detected. During the period of spastic paralysis, changes in the blood may be absent.