European bluetongue serotype 8

Disease threat assessment for U.S. sheep

Barbara S. Drolet*, Lindsey M. Reister-Hendricks, Brendan K. Podell, Jonathan E. Breitenbach, D.S. Mcvey, Piet A. van Rijn, Richard A. Bowen

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotypes have been detected in livestock and wildlife in the past 16 years. Introductions of serotypes, with unknown virulence and disease risk, are constant threats to US agriculture. One potential incursive serotype of particular concern is the European strain of BTV-8, which was introduced into Northern Europe in 2006 and caused unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess disease risk of BTV-8 in a common white-faced American sheep breed, eight Polled Dorset yearlings were experimentally infected and monitored for clinical signs. Viremia and viral tissue distribution were detected and quantified by real-time qRT-PCR. Overall, clinical disease was moderate with no mortality. Viremia reached as high as 9.7 log10 particles/mL and persisted at 5 logs or higher through the end of the study (28 days). Virus distribution in tissues was extensive with the highest mean titers at the peak of viremia (day 8) in the kidney (8.38 log10 particles/mg) and pancreas (8.37 log10 particles/mg). Virus persisted in tissues of some sheep at 8 logs or higher by day 28. Results of this study suggest that should BTV-8 emerge in the United States, clinical disease in this common sheep breed would likely be similar in form, duration, and severity to what is typically observed in severe outbreaks of endemic serotypes, not the extraordinary disease levels seen in Northern Europe. In addition, a majority of exposed sheep would be expected to survive and act as significant BTV-8 reservoirs with high titer viremias for subsequent transmission to other livestock and wildlife populations.

Original languageEnglish
Pages (from-to)400-407
JournalVector-Borne and Zoonotic Diseases
Volume16
Issue number6
DOIs
Publication statusPublished - 2016

Fingerprint

Bluetongue
Bluetongue virus
Sheep
Viremia
Livestock
Ceratopogonidae
Tissue Distribution
Mortality
Orbivirus
Viruses
Deer
Agriculture
Disease Outbreaks
Virulence
Serogroup
Real-Time Polymerase Chain Reaction
Pancreas
Morbidity
Kidney
Population

Keywords

  • Bluetongue virus
  • BTV-8
  • Orbivirus
  • Sheep
  • U.S.

Cite this

Drolet, B. S., Reister-Hendricks, L. M., Podell, B. K., Breitenbach, J. E., Mcvey, D. S., van Rijn, P. A., & Bowen, R. A. (2016). European bluetongue serotype 8: Disease threat assessment for U.S. sheep. Vector-Borne and Zoonotic Diseases, 16(6), 400-407. https://doi.org/10.1089/vbz.2015.1924
Drolet, Barbara S. ; Reister-Hendricks, Lindsey M. ; Podell, Brendan K. ; Breitenbach, Jonathan E. ; Mcvey, D.S. ; van Rijn, Piet A. ; Bowen, Richard A. / European bluetongue serotype 8 : Disease threat assessment for U.S. sheep. In: Vector-Borne and Zoonotic Diseases. 2016 ; Vol. 16, No. 6. pp. 400-407.
@article{75e2813a7c494860bcd5208986d75b77,
title = "European bluetongue serotype 8: Disease threat assessment for U.S. sheep",
abstract = "Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotypes have been detected in livestock and wildlife in the past 16 years. Introductions of serotypes, with unknown virulence and disease risk, are constant threats to US agriculture. One potential incursive serotype of particular concern is the European strain of BTV-8, which was introduced into Northern Europe in 2006 and caused unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess disease risk of BTV-8 in a common white-faced American sheep breed, eight Polled Dorset yearlings were experimentally infected and monitored for clinical signs. Viremia and viral tissue distribution were detected and quantified by real-time qRT-PCR. Overall, clinical disease was moderate with no mortality. Viremia reached as high as 9.7 log10 particles/mL and persisted at 5 logs or higher through the end of the study (28 days). Virus distribution in tissues was extensive with the highest mean titers at the peak of viremia (day 8) in the kidney (8.38 log10 particles/mg) and pancreas (8.37 log10 particles/mg). Virus persisted in tissues of some sheep at 8 logs or higher by day 28. Results of this study suggest that should BTV-8 emerge in the United States, clinical disease in this common sheep breed would likely be similar in form, duration, and severity to what is typically observed in severe outbreaks of endemic serotypes, not the extraordinary disease levels seen in Northern Europe. In addition, a majority of exposed sheep would be expected to survive and act as significant BTV-8 reservoirs with high titer viremias for subsequent transmission to other livestock and wildlife populations.",
keywords = "Bluetongue virus, BTV-8, Orbivirus, Sheep, U.S.",
author = "Drolet, {Barbara S.} and Reister-Hendricks, {Lindsey M.} and Podell, {Brendan K.} and Breitenbach, {Jonathan E.} and D.S. Mcvey and {van Rijn}, {Piet A.} and Bowen, {Richard A.}",
year = "2016",
doi = "10.1089/vbz.2015.1924",
language = "English",
volume = "16",
pages = "400--407",
journal = "Vector-Borne and Zoonotic Diseases",
issn = "1530-3667",
publisher = "Mary Ann Liebert",
number = "6",

}

Drolet, BS, Reister-Hendricks, LM, Podell, BK, Breitenbach, JE, Mcvey, DS, van Rijn, PA & Bowen, RA 2016, 'European bluetongue serotype 8: Disease threat assessment for U.S. sheep', Vector-Borne and Zoonotic Diseases, vol. 16, no. 6, pp. 400-407. https://doi.org/10.1089/vbz.2015.1924

European bluetongue serotype 8 : Disease threat assessment for U.S. sheep. / Drolet, Barbara S.; Reister-Hendricks, Lindsey M.; Podell, Brendan K.; Breitenbach, Jonathan E.; Mcvey, D.S.; van Rijn, Piet A.; Bowen, Richard A.

In: Vector-Borne and Zoonotic Diseases, Vol. 16, No. 6, 2016, p. 400-407.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - European bluetongue serotype 8

T2 - Disease threat assessment for U.S. sheep

AU - Drolet, Barbara S.

AU - Reister-Hendricks, Lindsey M.

AU - Podell, Brendan K.

AU - Breitenbach, Jonathan E.

AU - Mcvey, D.S.

AU - van Rijn, Piet A.

AU - Bowen, Richard A.

PY - 2016

Y1 - 2016

N2 - Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotypes have been detected in livestock and wildlife in the past 16 years. Introductions of serotypes, with unknown virulence and disease risk, are constant threats to US agriculture. One potential incursive serotype of particular concern is the European strain of BTV-8, which was introduced into Northern Europe in 2006 and caused unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess disease risk of BTV-8 in a common white-faced American sheep breed, eight Polled Dorset yearlings were experimentally infected and monitored for clinical signs. Viremia and viral tissue distribution were detected and quantified by real-time qRT-PCR. Overall, clinical disease was moderate with no mortality. Viremia reached as high as 9.7 log10 particles/mL and persisted at 5 logs or higher through the end of the study (28 days). Virus distribution in tissues was extensive with the highest mean titers at the peak of viremia (day 8) in the kidney (8.38 log10 particles/mg) and pancreas (8.37 log10 particles/mg). Virus persisted in tissues of some sheep at 8 logs or higher by day 28. Results of this study suggest that should BTV-8 emerge in the United States, clinical disease in this common sheep breed would likely be similar in form, duration, and severity to what is typically observed in severe outbreaks of endemic serotypes, not the extraordinary disease levels seen in Northern Europe. In addition, a majority of exposed sheep would be expected to survive and act as significant BTV-8 reservoirs with high titer viremias for subsequent transmission to other livestock and wildlife populations.

AB - Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotypes have been detected in livestock and wildlife in the past 16 years. Introductions of serotypes, with unknown virulence and disease risk, are constant threats to US agriculture. One potential incursive serotype of particular concern is the European strain of BTV-8, which was introduced into Northern Europe in 2006 and caused unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess disease risk of BTV-8 in a common white-faced American sheep breed, eight Polled Dorset yearlings were experimentally infected and monitored for clinical signs. Viremia and viral tissue distribution were detected and quantified by real-time qRT-PCR. Overall, clinical disease was moderate with no mortality. Viremia reached as high as 9.7 log10 particles/mL and persisted at 5 logs or higher through the end of the study (28 days). Virus distribution in tissues was extensive with the highest mean titers at the peak of viremia (day 8) in the kidney (8.38 log10 particles/mg) and pancreas (8.37 log10 particles/mg). Virus persisted in tissues of some sheep at 8 logs or higher by day 28. Results of this study suggest that should BTV-8 emerge in the United States, clinical disease in this common sheep breed would likely be similar in form, duration, and severity to what is typically observed in severe outbreaks of endemic serotypes, not the extraordinary disease levels seen in Northern Europe. In addition, a majority of exposed sheep would be expected to survive and act as significant BTV-8 reservoirs with high titer viremias for subsequent transmission to other livestock and wildlife populations.

KW - Bluetongue virus

KW - BTV-8

KW - Orbivirus

KW - Sheep

KW - U.S.

U2 - 10.1089/vbz.2015.1924

DO - 10.1089/vbz.2015.1924

M3 - Article

VL - 16

SP - 400

EP - 407

JO - Vector-Borne and Zoonotic Diseases

JF - Vector-Borne and Zoonotic Diseases

SN - 1530-3667

IS - 6

ER -