|JOHNSON, D - Animal And Plant Health Inspection Service (APHIS)|
|OSTLUND, E - Animal And Plant Health Inspection Service (APHIS)|
|CHASE, C - South Dakota State University|
|STALLKNECHT, D - University Of Georgia|
Submitted to: Veterinaria Italiana
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/15/2015
Publication Date: 12/31/2015
Publication URL: http://doi:10.12834/VetIt.555.2627.1
Citation: Wilson, W.C., Gaudreault, N.N., Jasperson, D.C., Johnson, D., Ostlund, E., Chase, C.L., Ruder, M.G., Stallknecht, D.E. 2015. Molecular evolution of American field strains of bluetongue and epizootic hemorrhagic disease viruses. Veterinaria Italiana. 51(4):269-273.
Interpretive Summary: Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are insect-transmitted viruses that cause disease in domestic and wild ruminant. They cross national boundaries (transboundary) and can cause significant animal disease and economic trade losses. This paper summarizes a series of studies looking at variation in the whole virus genome sequences to understand the movement and genetic relatedness of viruses in the Americas. This provides insight into the biology of these viruses and information of use to those responsible for managing animal health disease risks.
Technical Abstract: Recent Orbivirus events in the Americas have been investigated using whole genome amplification and sequencing followed by phylogenetic analysis. These studies utilized an unbiased amplification protocol that allows the whole bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) genomes to be amplified without prior sequence knowledge and subjected to next generation DNA sequencing. This technology was applied to evaluate BTV-3 isolates spanning four decades from Florida, Arkansas, Mississippi, South Dakota, Central America, and the Caribbean basin. Results of the dataset analysis are consistent with the hypothesis that these viruses were introduced into the United States from Central America and the Caribbean basin. A similar analysis was performed on a recent BTV-2 isolate from California. Those results indicated that this BTV-2 strain was likely introduced into Florida then moved south to the Caribbean and west to California. A historical (1955-2012) molecular characterization of EHDV strains was also completed, and subsequently used as reference sequences for comparison of genomes from recent 2012 cattle isolates that were associated with clinical disease. Finally, this analysis was performed on BTV-11 isolated from two separate canine cases, and demonstrated that the genome sequences of the virus isolates from these cases were almost identical. These studies indicate the value of this technology in understanding virus epidemiology and ecology.