“886-84-like” tick-borne encephalitis virus strains: Intraspecific status elucidated by comparative genomics

Tick-borne encephalitis virus (TBEV) can cause severe meningitis, encephalitis, and meningoencephalitis. TBEV represents a pathogen of high zoonotic potential and an emerging global threat. There are three known subtypes of TBEV: Far-Eastern, Siberian and European. Since 2001 there have been suggestions that two new subtypes may be distinguished: “178-79” and “886-84”. These assumptions are based on the results of the envelope gene fragment sequencing (Zlobin et al., 2001; Kovalev and Mukhacheva, 2017) and genotype-specific probes molecular hybridization (Demina et al., 2010). There is only one full-genome sequence of “178-79” strain and two identical ones of “886-84” strain can be found in GenBank. For clarification of the intraspecific position of the "886-84-like" strains group we completely sequenced six previously unknown “886-84-like” strains isolated in Eastern Siberia. As a result of applying different bioinformatics approaches, we can confirm that "886-84-like" strains group is a distinct subtype of TBEV.