Molecular epidemiology and evolution of fish Novirhabdoviruses




The genus Novirhabdoviridae contains several of the important rhabdoviruses that infect fish hosts. There are four established virus species: Infectious hematopoietic necrosis virus (IHNV), Viral hemorrhagic septicemia virus (VHSV), Hirame rhabdovirus(HIRRV), and Snakehead rhabdovirus (SHRV). Viruses of these species vary in host and geographic range, and they have all been studied at the molecular and genomic level. As globally significant pathogens of cultured fish, IHNV and VHSV have been particularly well studied in terms of molecular epidemiology and evolution. Phylogenic analyses of hundreds of field isolates have defined five major genogroups of IHNV and four major genotypes of VHSV worldwide. These phylogenies are informed by the known histories of IHNV and VHSV, each involving a series of viral emergence events that are sometimes associated with host switches, most often into cultured rainbow trout. In general, IHNV has relatively low genetic diversity and a narrow host range, and has been spread from its endemic source in North American to Europe and Asia due to aquaculture activities. In contrast, VHSV has broad host range and high genetic diversity, and the source of emergence events is virus in widespread marine fish reservoirs in the northern Atlantic and Pacific Oceans. Common mechanisms of emergence and host switch events include use of raw feed, proximity to wild fish reservoirs of virus, and geographic translocations of virus or naive fish hosts associated with aquaculture.

Additional publication details

Publication type Book chapter
Publication Subtype Book Chapter
Title Molecular epidemiology and evolution of fish Novirhabdoviruses
Year Published 2014
Language English
Publisher Caister Academic Press
Contributing office(s) Western Fisheries Research Center
Description 29 p.
Larger Work Type Book
Larger Work Title Rhabdoviruses: Molecular taxonomy, Evolution, Genomics, Ecology, Cytopathology, and Control
First page 89
Last page 117
Online Only (Y/N) N
Additional Online Files (Y/N) N