N.M. POPONIN, A.L. BONDARENKO

Kirov State Medical University of the Ministry of Health of the Russian Federation, Kirov

 Contact details:

Poponin N.M. — postgraduate student of the Department of Infectious Diseases

Address: 112 K. Marx St., Kirov, Russian Federation, 610998, tel.: +7 (8332) 33-03-98, e-mail: bucoleon@yandex.ru 

The purpose — study of the clinical and epidemiological picture and outcomes of tick-borne viral encephalitis in 2015–2017 on the territory of the Kirov Region.

Materials and methods. The study group included 135 patients with acute forms of infection aged 20 to 84 years. Fever form was observed in 53,9% of patients. Focal forms accounted for 36,7% of cases. In 9,4% of cases, a meningeal form was recorded. Condition of convalescents discharged with residual effects of tick-borne viral encephalitis was evaluated during the follow-up period after 3 and 6 months.

Results. Tick-borne viral encephalitis often affected young and middle-aged people (57,6%). Men prevailed among patients who had focal forms of the disease (52,6%). The transmission path was noted in 61,7%, the alimentary path — in 6,3%. 10,1% of patients shook ticks from clothing or skin. An unknown transmission route (21,9 ± 7,2% of cases) was more common with focal forms of the disease than with non-focal forms (38 ± 3,4% and 12,9 ± 1,8%, respectively, p < 0,05). The disease began acutely with severe intoxication-inflammatory syndrome. The following options were identified in the clinical structure of focal forms: polioencephalitic — 34,1%, poliomyelitic — 25,6%, polioencephalomyelitic — 16,2%, encephalitic — 11,9%, encephalopoliomyelitic — 10,4%, encephalopolioencephalitic — 1,8%. At the end of focal formaresis or severe weakness of the predominantly upper extremities were observed in 38,2% of cases, facial asymmetry, ptosis of the eyelids, tongue deviation in 27,7%, ataxia in 22,8%, tremor of the tongue or hand in 21,4%. In 1,9% of cases, fatal outcome was recorded.

Conclusion. Tick-borne viral encephalitis is an endemic disease for the Kirov Region, mainly with a vector-borne transmission of infection. An unknown transmission route is a risk factor for the development of focal forms. Focal forms are found in 36.7% of cases, with residual effects 64,9% of patients are discharged.

Key words: tick-borne viral encephalitis, clinic, outcomes. 

(For citation: Poponin N.M., Bondarenko A.L. Tick-borne encephalitis in the Kirov Region: epidemiology, clinical picture and outcomes. Practical Medicine. 2019.  Vol. 17, № 7, P. 143-148)

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