Figure 1. Phylogenetic tree of the envelope gene of tick-borne encephalitis (TBE) virus strains constructed by using PHYLIP software (http://evolution.genetics.washington.edu/phylip.html). Omsk hemorrhagic fever (OHF) virus was used as the out-group. The numbers at the nodes represent bootstrap values. LI, louping ill; SSE, Spanish sheep encephalitis; TSE, Turkish sheep encephalitis; GGE, Greek goat encephalitis. Scale bar, 10% nucleotide sequence divergence.