TABLE 5.
Analytical sensitivitya
| Sample (genotype) | Virus concnb (particles g−1c/RNA copies g−1d) | EIA | rRT-PCR (CT) | EM (no. of particles) | Minimum detectable virus concne |
|
|---|---|---|---|---|---|---|
| No. of particles g−1 | No. of RNA copies g−1 | |||||
| A (GII.4) | 2.09E+08/1.15E+10 | + | 21.3 | 52,557 | 2.10E+07 | 1.15E+09 |
| B (GII.4) | 6.80E+07/2.07E+09 | + | 23.9 | 16,969 | 6.80E+06 | 2.07E+08 |
| C (GII.4) | 2.10E+09/5.85E+09 | + | 25.6 | 52,321 | 2.09E+07 | 5.85E+07 |
| Avg for A, B, and C | 1.62E+07 | 4.20E+08 | ||||
| D (GI.4) | 2.12E+08/1.03E+10 | + | 23.6 | 5,303 | 2.12E+06 | 1.03E+08 |
| E (GI.4) | 4.94E+06/6.45E+06 | + | 27.9 | 12,370 | 4.94E+06 | 6.45E+06 |
| F (GI.4) | 2.15E+08/1.41E+09 | + | 25.3 | 53,735 | 2.15E+06 | 1.41E+07 |
| Avg for D, E, and F | 3.07E+06 | 4.12E+07 | ||||
a
Based on the minimum number of EM-detectable virus particles and NoV RNA copies detected by rRT-PCR required for a positive signal in the EIA (limit of detection).
b
The number of viral particles and number of RNA copies per g of fecal sample in the original (undiluted) specimen.
c
Particle counts were calculated based on the EM results.
d
The number of NoV RNA copies per g were calculated based on the number of copies/μl in a 20% suspension.
e
The number of viral particles or NoV RNA copies per g of fecal sample in the highest dilution positive by EIA.