TABLE 1.
Susceptibility to Oseltamivir of Influenza A and B Virus Isolates.
| Patient | Isolation year |
Influenza subtype |
Day of sample collection* |
Susceptibility to oseltamivir (mean IC50 ± SD, nM)¤ |
NA mutations |
|---|---|---|---|---|---|
| 1 | 2008 | A (H3N2) |
−1 | 0.41 ± 0.11 | NT |
| 16 | 0.83 ± 0.97 | NT | |||
| 2 | 2002 | A (H3N2) |
5 | 137.25 ± 7.14 | E119V |
| 8 | 134.37 ± 29.41 | E119V | |||
| 3 | 2004 | A (H3N2) |
−1 | 0.67 ± 0.42 | NT |
| 25 | 0.39 ± 0.22 | NT | |||
| 39 | 0.85 ± 0.23 | NT | |||
| 97 | 0.83 ± 0.19 | NT | |||
| 4 | 2008 | A (H3N2) |
0 | 0.54 ± 0.45 | NT |
| 5 | 2002 | A (H3N2) |
0 | 0.32 ± 0.10 | NT |
| 6 | 0.25 ± 0.08 | NT | |||
| 6 | 2008 | A (H3N2) |
2 | 0.31 ± 0.16 | ‡ |
| 4 | 0.30 ± 0.05 | E119G/E119V§ | |||
| 7 | 180.26 ± 76.48 | E119V | |||
| 7 | 2005 | A (H3N2) |
−1 | 183.35 ± 9.73 | E119V |
| 8 | 2008 | A (H3N2) |
−1 | 2.99 ± 0.63 | NT |
| 15 | 0.45 ± 0.24 | NT | |||
| 26 | 0.75 ± 0.41 | NT | |||
| 9 | 2008 | A (H1N1) |
−1 | 0.98 ± 0.37 | NT |
| 10 | 2005 | B | −3 | 12.00 ± 18.04 | NT |
| 11 | 2003 | B | −2 | 42.27 ± 15.62 | NT |
| 5 | 31.68 ± 20.00 | NT | |||
| 12 | 2003 | B | 0 | 731.86 ± 155.12 | N294S |
| 25 | 772.75 ± 103.57 | N294S |
*
With respect to the first day of antiviral therapy.
¤
All influenza viruses were susceptible to zanamivir (mean IC50 values range from 0.01 to 0.84, nM).
‡
No mutations were detected.
§
Mixed quasi-species. Amino acid numbering is based on N2 NA.
SD indicates standard deviation; NT indicates not tested.