Structure and Peculiarities of a Clinical Course of Tick-Borne Infections in Children of the Irkutsk Region

At present there are few studies generalizing the clinical picture of infections, transmitted by Ixodid ticks, in children population. Tick-borne viral encephalitis is still one of the important natural focal infections and accounts for up to 27 % among other tick-borne infections.

The aim of the study was to determine the structure and features of the clinical course of tick infections in children of the Irkutsk region.

Materials and methods. We conducted a retrospective analysis of 58 cases over three-year period from 2015 to 2017 of children aged 1 to 18 years diagnosed with tick-borne viral encephalitis (TVE), ixodid tick-borne borreliosis (ITB), tick-borne rickettsiosis (TR) according to the data of Irkutsk Regional Infectious Clinical Hospital.

Results and discussion. Among tick-borne infections, TVE was found in 43 % of cases, ITB – in 27.5 %, TR – in 29.5 %, there was one case of mixed infection: TVE + tick-borne typhus in North Asia. In TVE, feverish form was found in 40 % of cases, meningeal form – in 36 %, meningoencephalitic form – in 20 %, polyradiculonevritic form – in 4 %. Medium severity was observed in 56 % of cases, severe – in 28 %. In ITB, non-erythematous form was revealed in 62.5 % of cases, erythematous – in 12.5 %. Clinical and epidemiological TR was registered in 18 % of cases. In patients with TVE recovery was observed in 84 %, however, there were 4 % of neurological complications. With the diagnosis of ITB and TR, almost all children were discharged in a satisfactory condition. No deaths were reported within 3 years. According to the medical history: only 1 child was vaccinated against TVE, 2 children underwent seroprevention; ticks, who bit 4 patients, were studied. Medical history showed that 57 % of children had tick bites, and 7 % of cases associated the disease with consumption of non-boiled goat or cow milk. Residents of Irkutsk, Angarsk and Shelekhov comprised 47 %, residents of the Irkutsk region – 53 %. The most common localization of bites is the head and neck.

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