Table 1 Number (n) and percentage (%) of swIAV positive (Ct < 40) samples and samples with Ct-values (Ct ≤ 33) by influential factors viral load, swIAV subtype, stabilizer type, time after spiking and temperature
Factors | Parameter | swIAV RNA positive | Ct-values ≤ 33 |
|---|---|---|---|
Viral load | High | 63/64 (98%) | 53/63 (84%) |
Low | 46/64 (72%) | 23/46 (50%) | |
swIAV subtype | H1avN2 | 56/64 (88%) | 40/56 (71%) |
H1pdmN2 | 53/64 (83%) | 36/53 (68%) | |
Stabilizer | Yes | 90/96 (94%) | 64/90 (71%) |
No (Control) | 19/32 (59%) | 12/19 (63%) | |
NucleoProtect VET Reagent® | 29/32 (91%) | 20/29 (69%) | |
Primestore® | 29/32 (91%) | 21/29 (72%) | |
Sigma-Virocult® | 32/32 (100%) | 23/32 (72%) | |
Time after spiking | 0 h | 32/32 (100%) | 32/32 (100%) |
72 h | 27/32 (84%) | 17/27 (63%) | |
168 h (7 d) | 27/32 (84%) | 15/27 (56%) | |
336 h (14 d) | 23/32 (72%) | 12/23 (52%) | |
Temperature | 4 °C | 57/64 (89%) | 42/57 (74%) |
22 °C | 52/64 (81%) | 34/52 (65%) |