[Tick-borne encephalitis virus as an amplifier of the metamorphosis of Ixodes ricinus (Acari: Ixodidae) tick nymphs under long-day photoperiodic conditions].

: The metamorphosis of tick-borne encephalitis virus (TBEV)-induced I. ricinus nymphs under long-day photoperiodic conditions (18 light hours and 6 darkness hours) occurs more rapidly than in uninfected specimens. The infected nymphs begin to develop to the imagoes 25-33 days earlier than do uninfected ones. The first imagoes from the infected nymphs emerge on day 24 after saturation whereas those from the uninfected nymphs appear on day 43. The interval from nymphal saturation to imago development in 50% specimens is 27.7 +/- 2.0 and 52.2 +/- 0.7 days, respectively. Reasons for geographical differences in the intensity of amplification of the metamorphosis of saturated I. nicinus nymphs are discussed in the paper.