Display options
Share it on

Front Vet Sci. 2015 Sep 14;2:32. doi: 10.3389/fvets.2015.00032. eCollection 2015.

Objects in Contact with Classical Scrapie Sheep Act as a Reservoir for Scrapie Transmission.

Frontiers in veterinary science

Timm Konold, Stephen A C Hawkins, Lisa C Thurston, Ben C Maddison, Kevin C Gough, Anthony Duarte, Hugh A Simmons

Affiliations

  1. Animal Sciences Unit, Animal and Plant Health Agency Weybridge , Addlestone , UK.
  2. Pathology Department, Animal and Plant Health Agency Weybridge , Addlestone , UK.
  3. Surveillance and Laboratory Services, Animal and Plant Health Agency Penrith , Penrith , UK.
  4. ADAS UK, School of Veterinary Medicine and Science, University of Nottingham , Sutton Bonington , UK.
  5. School of Veterinary Medicine and Science, University of Nottingham , Sutton Bonington , UK.

PMID: 26664961 PMCID: PMC4672192 DOI: 10.3389/fvets.2015.00032

Abstract

Classical scrapie is an environmentally transmissible prion disease of sheep and goats. Prions can persist and remain potentially infectious in the environment for many years and thus pose a risk of infecting animals after re-stocking. In vitro studies using serial protein misfolding cyclic amplification (sPMCA) have suggested that objects on a scrapie-affected sheep farm could contribute to disease transmission. This in vivo study aimed to determine the role of field furniture (water troughs, feeding troughs, fencing, and other objects that sheep may rub against) used by a scrapie-infected sheep flock as a vector for disease transmission to scrapie-free lambs with the prion protein genotype VRQ/VRQ, which is associated with high susceptibility to classical scrapie. When the field furniture was placed in clean accommodation, sheep became infected when exposed to either a water trough (four out of five) or to objects used for rubbing (four out of seven). This field furniture had been used by the scrapie-infected flock 8 weeks earlier and had previously been shown to harbor scrapie prions by sPMCA. Sheep also became infected (20 out of 23) through exposure to contaminated field furniture placed within pasture not used by scrapie-infected sheep for 40 months, even though swabs from this furniture tested negative by PMCA. This infection rate decreased (1 out of 12) on the same paddock after replacement with clean field furniture. Twelve grazing sheep exposed to field furniture not in contact with scrapie-infected sheep for 18 months remained scrapie free. The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.

Keywords: classical scrapie; field furniture; prion; reservoir; serial protein misfolding cyclic amplification; sheep; transmissible spongiform encephalopathy

References

  1. Nat Protoc. 2012 Jun 28;7(7):1397-409 - PubMed
  2. Vet Rec. 2006 Oct 7;159(15):473-9 - PubMed
  3. Emerg Infect Dis. 2004 Jun;10(6):1003-6 - PubMed
  4. J Virol. 2011 Sep;85(17):9031-8 - PubMed
  5. J Virol. 2011 Jul;85(13):6309-18 - PubMed
  6. J Environ Qual. 2011 Mar-Apr;40(2):449-61 - PubMed
  7. J Vis Exp. 2014 Jan 19;(83):e51101 - PubMed
  8. J Infect Dis. 2010 Jun 1;201(11):1672-6 - PubMed
  9. Vet Res. 2011 May 18;42:65 - PubMed
  10. J Virol. 2010 Nov;84(21):11560-2 - PubMed
  11. Rev Sci Tech. 2003 Apr;22(1):121-43 - PubMed
  12. PLoS Pathog. 2015 Feb 09;11(2):e1004638 - PubMed
  13. Vet J. 2000 Jan;159(1):10-7 - PubMed
  14. Mol Biotechnol. 2009 Mar;41(3):254-62 - PubMed
  15. Vet Rec. 2015 Jan 24;176(4):99 - PubMed
  16. PLoS Pathog. 2006 Apr;2(4):e32 - PubMed
  17. Prion. 2012 Jan-Mar;6(1):52-61 - PubMed
  18. BMC Vet Res. 2008 Apr 08;4:14 - PubMed
  19. BMC Vet Res. 2009 Feb 10;5:8 - PubMed
  20. Res Vet Sci. 2004 Jun;76(3):211-7 - PubMed
  21. PLoS One. 2009;4(3):e4848 - PubMed
  22. Science. 1982 Apr 9;216(4542):136-44 - PubMed
  23. Vet Rec. 2008 Mar 29;162(13):397-403 - PubMed
  24. BMC Vet Res. 2009 Oct 09;5:38 - PubMed
  25. J Gen Virol. 2006 Dec;87(Pt 12):3737-40 - PubMed
  26. PLoS Pathog. 2007 May 25;3(5):e66 - PubMed
  27. J Virol. 2012 Jan;86(1):566-71 - PubMed
  28. BMC Vet Res. 2009 Feb 25;5:9 - PubMed
  29. PLoS One. 2007 May 09;2(5):e435 - PubMed

Publication Types