Phylogenetic tree for the complete H gene sequences of representative CDVs plus those detected in cases 18133, 21261, 19876, and 25259 (shown in boxes). The unrooted tree was generated using the distance matrix program NEIGHBOR with the jumble option invoked. Distance values were calculated by the DNADIST program within the PHYLIP software package using the Kimura two parameter. Only bootstrap values greater than 70 are shown, and the branch lengths are proportionate to genetic distances. The country of origin of each CDV is indicated by a two- or three-letter abbreviation following the isolate designation; Chn, China; Jpn, Japan; Ger, Germany; SA, South Africa; USA, United States of America; Dnk, Denmark; Trk, Turkey; Twn, Taiwan; Gnd, Greenland; Sib, Siberia. Canine distemper viruses used for comparison with the country of origin and year of isolation (if known), plus the accession numbers, are as follows: A75/17 (USA, 1975), AF164967; black leopard (USA, 1991), Z47763; black panther, strain A92-6 (USA, 1992), Z54166; Chinese leopard, strain A92-27/4 (USA, 1992), Z54156; dog (USA, 1989), Z47762; dog 4513 (Ger), Z77673; dog (Taiwan), AY378091; dog Hamamatsu (Japan, 1992 to 1994), D85754; dog Yanaka (Japan, 1992 to 1994), D85755; dog 5804 (Germany, 1990), AY386315; dog 91A (Denmark, 1991), AF478544; dog 91B (Denmark, 1991), AF478546; dog 2544 (Germany, 1995), Z77672; dog (Turkey), AY093674; dog (China), AF172411; dog GR88 (Greenland, 1988), Z47760; dog 26D (Japan, 1999), AB040766; dog 5B (Japan, 1999), AY297453; dog 98-002 (Japan, 1998), AB025270; dog HM3 (Japan, 1999), AB040767; dog KDK-1 strain (Japan, 1991), AB025271; dog Ueno (Japan, 1992 to 1994), D85753; ferret (German, 1989), X84999; giant panda (China), AF178038; javelina (USA, 1989), Z47764; lesser panda (China), AF178039; mink (Denmark, 1986), Z47759; Onderstpoort (South Africa), AF378705; PDV-2 Siberian seal (Siberia, 1988), X8499; raccoon 98-2646 (USA, 1988), AY542312 (also represents raccoon 98-2655 [USA, 1998], AY548109, and raccoon 98-2666 [USA, 1998], AY548110); raccoon 01-2689 (USA, 2001), AY465925 (also represents raccoon 01-2690 [USA, 2001]); raccoon 00-2601 (USA, 2000), AY443350; raccoon 01-2641(USA, 2001), AY526496; raccoon 01-2676 (USA, 2001), AY498692; raccoon 98-2654 (USA, 1998), AY466011; raccoon (USA, 1989), Z47765; raccoon dog (Japan, 1996), AB016776; Snyder Hill (Germany), AF259552.