TABLE 1.
Summary of amantadine-resistant influenza A viruses characterized in this studya
| Source | Host/subtype | No. of samples tested | No. of samples with M2 substitution (position) |
|---|---|---|---|
| Wild bird | Dk/H1-H12 | 83 | 0 |
| Dk/H5N2 | 16 | 1 (Val27Ile) | |
| LPM | DkH3N2 | 13 | 9 (Val27Ile) |
| Dk/H3N6 | 2 | 0 | |
| Dk/H9N2 | 2 | 0 | |
| Ck/H3N2 | 8 | 8 (Val27Ile) | |
| Ck/H9N2 | 11 | 0 | |
| BPF | Ck/H9N2 | 37 | 0 |
| Dk/H9N2 | 11 | 1 (Val27Ile) | |
| Dk/H3N2 | 12 | 0 | |
| Human | Hu/H3N2 | 12 | 6 (Ser31Asn) |
| Total | 207 | 25 |
a
LPM, live poultry market; BPF, backyard poultry farm; Dk, duck; Ck, chicken; Hu, human.