“…18,21,24 However, IHC does not routinely detect very early cases of CWD in these tissues. 17,20 Various fluids, such as saliva, blood, urine, and cerebrospinal fluid (CSF) have been evaluated in animals for their use in preclinical antemortem detection of abnormal prions. 4,6,10,22 Due to the minute concentrations of infectious proteins in saliva, blood, and urine, detection of the misfolded infectious prion protein (PrP res ) has been limited or unsuccessful without the use of protein misfolding cyclic amplification (PMCA), which increases the concentration to a detectable level, and is orders of magnitude more sensitive for detecting PrP CWD than commonly used methods such as Western blotting and IHC, 7 enabling detection of minute amounts of infectious prions in animal tissues and environmental samples.…”