Detection of Prions in Blood of Cervids at the Asymptomatic Stage of Chronic Wasting Disease

Sci Rep. 2017 Dec 8;7(1):17241. doi: 10.1038/s41598-017-17090-x.


Chronic wasting disease (CWD) is a rapidly spreading prion disorder affecting captive and free-ranging cervids. The zoonotic potential of CWD is unknown, as well as the mechanism for its highly efficient transmission. A top priority to minimize further spreading of this disease and its potential impact on environmental prion contamination is the development of a non-invasive, sensitive, and specific test for ante-mortem detection of infected animals. Here, we optimized the protein misfolding cyclic amplification (PMCA) assay for highly efficient detection of CWD prions in blood samples. Studies were done using a blind panel of 98 field-collected samples of whole blood from codon 96 glycine/glycine, captive white-tailed deer that were analyzed for prion infection post-mortem by immunohistochemistry (IHC). The results showed a sensitivity of 100% in animals with very poor body condition that were IHC-positive in both brain and lymph nodes, 96% in asymptomatic deer IHC-positive in brain and lymph nodes and 53% in animals at early stages of infection that were IHC-positive only in lymph nodes. The overall mean diagnostic sensitivity was 79.3% with 100% specificity. These findings show that PMCA might be useful as a blood test for routine, live animal diagnosis of CWD.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Asymptomatic Diseases*
  • Blood Chemical Analysis / methods*
  • Deer*
  • Limit of Detection
  • Prions / blood*
  • Wasting Disease, Chronic / blood*


  • Prions