Submitted to: Prion
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/29/2011
Publication Date: 1/1/2012
Citation: Tamguney, G., Richt, J.A., Hamir, A.N., Greenlee, J.J., Miller, M.W., Wolfe, L.L., Sirochman, T.M., Young, A.J., Glidden, D.V., Johnson, N.L., Giles, K., Dearmond, S.J., Prusiner, S.B. 2012. Salivary prions in sheep and deer. Prion. 6(1):52-61. Interpretive Summary: Scrapie is a neurodegenerative disease of sheep and goats that is caused by infectious agents called prions. This manuscript identifies saliva as a potential route of scrapie transmission. When saliva from sheep clinically affected with scrapie is inoculated into the brain of mice expressing an ovine prion gene, a high percentage of the mice develop scrapie. This provides evidence that sheep saliva contains infectious prions, however, additional experiments will be required to determine if the infectivity of sheep saliva is sufficient to cause scrapie transmission under natural conditions. Results of this study will potentially impact sheep producers and regulatory agencies involved in scrapie prevention since this is significant new information about scrapie transmission.
Technical Abstract: Scrapie is a prion disease transmitted naturally within affected host populations of sheep and goats. Although milk and placenta have been identified as sources of contagion for scrapie prions, these sources seem insufficient to explain either indirect or interspecies scrapie transmission. Here we show that scrapie-infected sheep secrete prions in their saliva, thereby providing a plausible natural shedding mechanism that might explain the horizontal transmission of scrapie.