Table 3.
SARS-CoV-2 recovery from sewage samples concentrated by PEG precipitation and PAC flocculation.
| Concentration method | SARS-CoV-2 seeded (GC/mL) | SARS-CoV-2 recovered |
Mean recovery (%) (range) | ||
|---|---|---|---|---|---|
| Detection (n detected/n tested) |
Mean concentration (GC/mL) ± SDa | ||||
| N1 gene | N2 gene | ||||
| PEG precipitation (Method 7) | 4.3 × 103 | 3/3 | 3/3 | 3.2 × 102 ± 3.4 × 102 | 7.4 (2.7–16.7) |
| 4.3 × 102 | 2/3 | 0/3 | 4.0 × 101 ± 6.3 × 101 | 9.4 (0–26.4) | |
| 4.3 × 101 | 0/3 | 0/3 | 0 | 0 | |
| PAC flocculation (Method 8) | 4.3 × 103 | 3/3 | 3/3 | 3.9 × 102 ± 4.5 × 102 | 9.2 (0.7–21.0) |
| 4.3 × 102 | 3/3 | 3/3 | 1.7 × 102 ± 2.0 × 102 | 38.8 (7.8–93.6) | |
| 4.3 × 101 | 0/3 | 0/3 | 0 | 0 | |
a
SD: standard deviation.