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

Abstract

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.Conclusion. There is a low public commitment to the vaccine prevention of tick-borne infections. Therefore, it is necessary to promote both specific and non-specific prevention of tick-borne encephalitis among children of the Irkutsk region.

Keywords

• tick-borne viral encephalitis
• ixodid tick-borne borreliosis
• tick-borne rickettsiosis
• vaccine prophylaxis