|O Hearn, Emily|
Submitted to: United States Animal Health Association Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/24/2007
Publication Date: 8/1/2008
Publication URL: http://www.usaha.org/Portals/6/Reports/2007/report-btbr-2007.pdf
Citation: Wilson, W.C., Drolet, B.S., Kato, C.Y., Harpster, M.H., Bennett, K.E., O Hearn, E.S., Reeves, W.K., Mecham, J.O., Miller, M.M. 2008. Report of the Bluetongue and Bovine Retroviruses Committee. United States Animal Health Association Proceedings,Reno, NV, October 18-24, 2007, 111:207-208. Interpretive Summary: Arthropod-Borne Animal disease Research Laboratory scientists made presentations during the U.S. Animal Health Association’s Bluetongue and Bovine Retroviruses Committee meeting at the annual meeting. Dr. Barbara Drolet presented an update of the ABADRL facility renovations and ongoing ABADRL research. Dr. James Mecham discussed research on the interactions of BTV with vertebrate cells. Dr. Will Reeves presented that there was no evidence for persistence of the recently introduced Bluetongue Virus (BTV) seryotype 1 in Southern Louisiana. Dr. William Wilson presented a new genetic amplification assay for detection and distinction of BTV and the related Epizootic Hemorrhagic Disease Viruses.
Technical Abstract: Characterizing the Epidemiology of Bluetongue Virus Serotype 1 in Southern Louisiana. Will K. Reeves, Mike Becker, Cecilia Kato, Richard Mayer, and Lane D. Foil. In November 2004, BTV-1 was isolated from the tissues of a hunter-killed white tailed deer from southern Louisiana. There was significant concern that BTV-1 might be established in Louisiana. Unfortunately, the hurricanes season of 2005 caused so much devastation that monitoring the status of BTV-1 in southern Louisiana was impossible. Culicoides spp. were sampled from southern Louisiana in 2006 and 2007. Four pools of Culicoides tested positive for BTV but the virus serotype appears to be BTV-17. The reason for the disappearance of BTV-1 from Louisiana remains unknown. Analysis and characterization of the receptor for bluetongue virus on vertebrate cells. James Mecham. The research at the Animal Diseases Research Laboratory (ABADRL) on characterization of mammalian cell receptor(s) for bluetongue virus was presented. Experiments with glycan deficient cells and competitive inhibitors suggest the involvement of specific glycans in the initial interaction of virus with susceptible cells. The data also indicate that this initial interaction facilitates or enhances virus binding to a secondary receptor, which is required for virus internalization. Understanding the nature of viral receptors on susceptible cells will enhance our understanding of tissue trophism and pathology and may lead to more effective disease control strategies. Molecular diagnostic tools for early detection of arthropod-borne animal viruses. William C. Wilson, Emily S. O’Hearn, Raymond Lenhoff, Ben Hindson, Clinton Torres, David Stallknecht, Daniel Mead, and James O. Mecham. An update was presented on the Arthropod-Borne Animal Diseases Research Laboratory efforts on the development of rapid nucleic acid detection tests for BTV and the related EHDV for all serotypes. This work has been done in collaboration with the Lawrence Livermore National Laboratories and the Southeastern Cooperative Wildlife Disease Study. Rapid real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) tests that detect prototype strains of indigenous and exotic BTV and EHDV RNA have been developed. The EHDV qRT-PCR detected all 40 field strains available. The EHDV qRT-PCR was evaluated against clinical samples, and could directly viral RNA from tissues were also virus isolation. The assay is slightly less sensitive than the nested RT-PCR previously developed by ABADRL but is not as prone to cross-contamination. An Update on the Arthropod-Borne Animal Diseases Research Laboratory, Laramie, WY. Barbara S. Drolet. The mission of the Arthropod-Borne Animal Diseases Research Laboratory (ABADRL) is to solve major emerging and/or exotic arthropod-borne disease problems that affect or threaten the U.S. livestock industry and wildlife. Currently the ABADRL is addressing research gaps of several arboviruses including domestic and exotic strains of bluetongue virus, epizootic hemorrhagic disease virus, vesicular stomatitis virus, and Rift Valley fever virus. Research areas include virus-vector-host interactions; development, refinement, evaluation and validation of diagnostic tests and vaccines; characterization of viral receptors on vertebrate and invertebrate cells; characterization of viral persistence in Culicoides; vector competence; horizontaand vertical arbovirus transmission; vector genomics and proteomics of insect salivary glands and midguts; vector biology, ecology, and behavior; disease risk assessment; and development of effective disease and vector control management strategies.