Molecular epidemiology of infectious hematopoietic necrosis virus reveals complex virus traffic and evolution within southern Idaho aquaculture.
Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus which infects salmon and trout and may cause disease with up to 90% mortality. In the Hagerman Valley of Idaho, IHNV is endemic or epidemic among numerous fish farms and resource mitigation hatcheries. A previous study characterizing the genetic diversity among 84 IHNV isolates at 4 virus-endemic rainbow trout farms indicated that multiple lineages of relatively high diversity co-circulated at these facilities (Troyer et al. 2000 J Gen Virol. 81:2823-2832). We tested the hypothesis that high IHNV genetic diversity and co-circulating lineages are present in aquaculture facilities throughout this region. In this study, 73 virus isolates from 14 rainbow trout farms and 3 state hatcheries in the Hagerman Valley, isolated between 1978 and 1999, were genetically characterized by sequence analysis of a 303 nucleotide region of the glycoprotein gene. Phylogenetic and epidemiological analyses showed that multiple IHNV lineages co-circulate in a complex pattern throughout private trout farms and state hatcheries in the valley. IHNV maintained within the valley appears to have evolved significantly over the 22 yr study period.
D000818:Animals; D017756:Aquaculture / Q000706:statistics & numerical data*; D001483:Base Sequence; D019143:Evolution, Molecular; D005393:Fish Diseases / Q000453:epidemiology* / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics*; D007061:Idaho / Q000453:epidemiology; D029142:Infectious hematopoietic necrosis virus / Q000145:classification / Q000235:genetics*; D017720:Molecular Epidemiology; D017686:Oncorhynchus mykiss / Q000821:virology*; D010802:Phylogeny; D012367:RNA, Viral / Q000032:analysis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D018353:Rhabdoviridae Infections / Q000453:epidemiology / Q000235:genetics / Q000662:veterinary*; D017421:Sequence Analysis / Q000662:veterinary; D015996:Survival Rate; D014774:Virulence / Q000235:genetics
D012367:RNA, Viral