TABLE 3.
Detection limits of the three real-time RT-PCR assays on the different clades of the influenza A(H1N1)pdm09 and A(H3N2) viruses
| Virus strain | Detection limit (M gene copies per reaction) of the indicated assay |
M gene variations at nucleotide positiona: |
HA clade | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Aw1 | Aw2b | At | 153 | 154 | 163 | 189 | 225 | 228 | 238 | ||
| A/TW/80125/2013 | 300 | 300 | 30 | —c | T | — | — | A | — | A | 11.1 |
| A/TW/80128/2013 | 750 | 75 | 37.5 | — | T | — | — | — | — | A | 11.1 |
| A/TW/80208/2013 | 315 | 315 | 15.8 | — | T | — | — | — | C | A | 12.1 |
| A/TW/80720/2013 | 3,500 | 350 | 17.5 | T | — | T | T | — | — | — | TW2011-13 |
a
The variations at the indicated positions were compared to the sequences of the primers and the probe used in the Aw1 assay.
b
Assay recommended by the WHO for the detection of A(H1N1)pdm09 viruses.
c
—, nucleotides that were identical to the sequences of the primers and the probe used in the Aw1 assay.