Preliminary Analytical Evaluation of PEDV- and PDCoV-Targeting Primer Probe Sets on a Cartridge-Based POCT RT qPCR Platform

Porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV) cause severe diarrhoea in piglets, requiring rapid laboratory differentiation. In this technical note, we evaluated primer–probe sets from Chinese quarantine industry standards on the Coyote Flash10 cartridge-based POCT combined primer–probe RT qPCR platform. Assays were characterised using a digitally PCR-quantified single-target in vitro transcribed viral RNA and RNA-spiked porcine faecal matrix. Exploratory low-concentration amplifications were observed at 3.222 copies/μL (PEDV) and 2.28 copies/μL (PDCoV); however, the corresponding Ct values fell within an indeterminate range, and no statistically validated limits of detection were established. The PEDV standard curve included concentrations with mean Ct values in the indeterminate and negative ranges, so its apparent efficiency was not considered a validated performance metric. PDCoV efficiency was sub-optimal (~77.7%). Low intra run Ct variability (CV < 3%) was observed in spiked matrix tests. No cross amplification was detected against four selected swine pathogens under the tested conditions. Notably, mixed-ratio co-template viral RNA experiments simulating co-infection were not performed. The proprietary internal control (IC) was recorded descriptively and was not used to assess extraction efficiency or sample validity. This work demonstrates preliminary analytical feasibility of this primer–probe combination on the Flash10 platform; full clinical diagnostic performance remains to be validated in further studies.