Shigapova et al. Genetic diversity of tick-borne encephalitis virus in Kyrgyzstan. Viruses. 2026;18(1):107. doi:10.3390/v18010107
Knowledge about the epidemiology of tick-borne encephalitis (TBE) virus and the clinical manifestations of TBE in Kyrgyzstan remains limited. Kyrgyzstan is in Central Asia and borders TBE-endemic regions of Kazakhstan and China.
Viral isolates originating from Ixodes persulcatus ticks collected in various regions of Kyrgyzstan in 1986 were analysed. Dendrogram analysis of the genomes of the isolated strains revealed that the Siberian (Sib) subtype is predominant, representing seven of the nine strains identified. Within the Sib subtype, three strains belonged to the Vasilchenko lineage, two to the Zausev lineage, and two to the Bosnia lineage.
In addition to the Sib strains, two isolates belonged to the Far Eastern (FE) subtype. The European, Baikalian, and Himalayan subtypes were not detected.
The detection of the FE subtype in Kyrgyzstan is consistent with findings from neighbouring regions, particularly China, where this subtype is also present. In contrast, data on TBE virus circulation in Uzbekistan and Tajikistan remain unavailable.
The Sib and FE subtype isolates identified in this study represent the current southernmost boundary of the geographical distribution of these TBE virus subtypes.