U.S. Concerns over Bluetongue

M. Enserink's News of the Week story “Exotic disease of farm animals tests Europe's responses” (8 February, p. [710][1]) describes how bluetongue, a disease caused by a vector-borne orbivirus, has spread widely in ruminant livestock in Europe since 1999. Unlike Europe, which has only experienced bluetongue disease in the past few years, the United States and the Americas in general have been endemic for several bluetongue virus (BTV) serotypes since first reported in the 1950s. The historically prevalent U.S. BTV serotypes, though pathogenic in sheep, have caused little to no disease in U.S. cattle. The vectors of these serotypes have been identified, and their distribution has in the past explained the epidemiology of BTV in the United States ([1][2]). ![Figure][3] Bluetongue virus particle. A computer model shows the crystalline structure of the core particle of BTV. CREDIT: DESY/PHOTO RESEARCHERS, INC. Recently, eight new serotypes of BTV and a new serotype of the related orbivirus, epizootic hemorrhagic disease virus (EHDV), have been identified in the United States ([2][4], [3][5]). Some of the virus isolates were from clinically affected sheep and deer, with others being detected through testing of cattle for export. The presence of these new serotypes raises the specter that the epidemiology of these viruses in North America may be changing and could result in more extensive disease in U.S. livestock and wildlife then ever seen previously. This is bad news for the U.S. livestock industries and for our ruminant wildlife. Our ability to understand the current situation is hindered because there is currently no comprehensive surveillance in the United States for either BTV or EHDV. A comprehensive surveillance system, greater risk assessment, and risk prevention through vaccine development and vector control are all needed. The events in Europe demand that we pay attention before BTV and EHDV have similar repercussions for the United States. 1. 1.[↵][6] 1. W. J. Tabachnick , Annu. Rev. Entomol. 41, 23 (1996). [OpenUrl][7][PubMed][8][Web of Science][9] 2. 2.[↵][10] 1. D. J. Johnson, 2. P. P. C. Mertens, 3. S. Maan, 4. E. N. Ostlund , in Proceedings of the 50th American Association of Veterinary Laboratory Diagnosticians (AAVLD) Annual Conference , Reno, NV, 18 to 23 October 2007, p. 118. 3. 3.[↵][11] 1. P. P. C. Mertens 2. et al. , 13th International Symposium WAVLD Conference Proceedings (2007), p. 55; [www.wavld2007.com/program.php][12]. [1]: /lookup/doi/10.1126/science.319.5864.710 [2]: #ref-1 [3]: pending:yes [4]: #ref-2 [5]: #ref-3 [6]: #xref-ref-1-1 View reference 1. in text [7]: {openurl}?query=rft.jtitle%253DAnnual%2Breview%2Bof%2Bentomology%26rft.stitle%253DAnnu%2BRev%2BEntomol%26rft.issn%253D0066-4170%26rft.aulast%253DTabachnick%26rft.auinit1%253DW.%2BJ.%26rft.volume%253D41%26rft.issue%253D1%26rft.spage%253D23%26rft.epage%253D43%26rft.atitle%253DCulicoides%2Bvariipennis%2Band%2BBluetongue%2BVirus%2BEpidemiology%2Bin%2Bthe%2BUnited%2BStates%26rft_id%253Dinfo%253Apmid%252F8546447%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [8]: /lookup/external-ref?access_num=8546447&link_type=MED&atom=%2Fsci%2F320%2F5878%2F872.1.atom [9]: /lookup/external-ref?access_num=A1996TP40300003&link_type=ISI [10]: #xref-ref-2-1 View reference 2. in text [11]: #xref-ref-3-1 View reference 3. in text [12]: http://www.wavld2007.com/program.php