Phylogenetic analysis of deer tick virus (DTV) strains based on a 257 nucleotide fragment of the E coding region. Newly isolated strains are denoted by “DTV WI07.” The neighbor-joining analysis with branch lengths proportional to Kimura 2-parameter distances. Numbers at each node are bootstrap confidence estimates based on 1,000 replicate analyses. GenBank accession numbers are as follows: DTV WI07*177 (pending submission), DTV WI07*254 (pending submission), DTV WI07*38 (pending submission), DTV WI07*5 (pending submission), DTV SPO B10 (af310921), DTV SPO (af135461), DTV Chippewa Falls (ay004079), POW WV77 (af310920), DTV CT (u93288), DTV Ipswich (u93289), POW ON62 (ay004074), POW LB (l06436), POW ON81 (ay004078).