Table 6.
Limit of detection of PEDV/PDCoV/TGEV/SADS-CoV/XIPC 5-plex PCR by testing serial dilutions of IVT RNAs.
| Genomic Copies per Reaction | PEDV/PDCoV/TGEV/SADS-CoV/XIPC 5-Plex PCR * | |
|---|---|---|
| PEDV N-gene IVT RNA | % (No. of Pos for PEDV) | Mean Ct (range) |
| 8 × 103 | 100% (3/3) | 24.28 (24.24–24.33) |
| 8 × 102 | 100% (3/3) | 27.71 (27.63–27.79) |
| 8 × 101 | 100% (20/20) | 31.35 (30.85–32.26) |
| 16 | 100% (20/20) | 33.76 (32.72–35.04) |
| 8 | 100% (20/20) | 34.55 (33.36–35.80) |
| 4 | 80% (16/20) | 35.7 (34.31–38.05) |
| 2 | 45% (9/20) | 37.53 (35.27–40) |
| 1 | 5% (1/20) | 38.70 (36.85–40) |
| PDCoV N-gene IVT RNA | % (No. of Pos for PDCoV) | Mean Ct (range) |
| 8 × 103 | 100% (3/3) | 24.02 (23.96–24.11) |
| 8 × 102 | 100% (3/3) | 27.64 (27.56–27.72) |
| 8 × 101 | 100% (3/3) | 31.41 (31.15–31.64) |
| 16 | 100% (20/20) | 33.95 (33.40–34.62) |
| 8 | 100% (20/20) | 34.93 (34.09–36.46) |
| 4 | 95% (19/20) | 36.24 (34.59–37.77) |
| 2 | 15% (3/20) | 37.92 (36.61–40) |
| 1 | 0% (0/20) | 38.71 (36.95–40) |
| TGEV S-gene IVT RNA | % (No. of Pos for TGEV) | Mean Ct (range) |
| 8 × 103 | 100% (3/3) | 25.28 (25.21–25.34) |
| 8 × 102 | 100% (3/3) | 28.81 (28.75–28.85) |
| 8 × 101 | 100% (3/3) | 32.71 (32.67–32.77) |
| 16 | 95% (19/20) | 35.75 (34.83–37.34) |
| 8 | 25% (5/20) | 37.47 (35.87–38.75) |
| 4 | 0% (0/20) | 39.16 (37.14–40) |
| 2 | 0% (0/20) | 39.79 (37.95–40) |
| 1 | 0% (0/20) | 39.96 (39.61–40) |
| SADS-CoV N-gene IVT RNA | % (No. of Pos for SADS-CoV) | Mean Ct (range) |
| 1.36 × 104 | 100% (3/3) | 23.87 (23.84–23.90) |
| 1.36 × 103 | 100% (3/3) | 27.27 (27.15–27.35) |
| 1.36 × 102 | 100% (3/3) | 30.65 (30.54–30.75) |
| 27.2 | 100% (20/20) | 32.91 (32.35–34.58) |
| 13.6 | 100% (20/20) | 34.23 (33.54–35.21) |
| 6.8 | 100% (20/20) | 35.41 (34.53–36.76) |
| 3.4 | 85% (17/20) | 36.38 (35.25–38.55) |
| 1.7 | 35% (7/20) | 37.93 (35.94–40) |
* The PEDV/PDCoV/TGEV/SADS-CoV/XIPC 5-plex PCR Ct < 37 was considered positive for each virus.