Yurchenko et al.
Phylogenetic analysis of tick-borne encephalitis virus strains found in an engorged tick and traveler returning from Russia.
Ticks Tick Borne Dis. 2021; 12:101670. doi.org/10.1016/j.ttbdis.2021.101670

A Ukrainian team has reported the rare case that TBE virus was first detected in an engorged tick and then the infection in the individual bitten by the tick.

A 55-year-old male spent time in Perm, Russia, and while traveling home to Odessa, Ukraine, found an engorged female Ixodes spp. tick on himself. Suckling mice were intracerebrally inoculated with tick suspension, and five days post inoculation, all animals exhibited signs of encephalitis. On the same day (eight days after the tick bite), blood was taken from the patient for virus isolation and antibody testing. The patient did not exhibit clinical signs, but the TBE virus could be detected and low TBE antibody titers. The patient received TBE immunoglobulins as part of post-exposure treatment, although it is generally recommended in Ukraine, that TBE immunoglobulins should not be administered later than on day 4 after tick bite. In this case, this late post-exposure treatment was successful as the treated individual remained healthy.

Phylogenetic analyses of the strain isolated from the tick and the patient revealed that it was Siberian subtype (Zausev group), and it showed high relationship to strains previously isolated near Perm.

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