Volume 19, Number 12—December 2013
Research
Antiviral Susceptibility of Highly Pathogenic Avian Influenza A(H5N1) Viruses Isolated from Poultry, Vietnam, 2009–2011
Table 2
Characterization of statistical outliers identified in neuraminidase inhibition assay*
Clade | Virus name | Neuraminidase gene change† | IC50, nmol/L; mean±SD (fold)‡ |
|||
---|---|---|---|---|---|---|
Oseltamivir | Zanamivir | Peramivir | Laninamivir | |||
1.1 |
A/ck/VN/NCVD-780/2011 | R430W | 0.69 ± 0.25 (12) | 18.89 ± 2.18 (73) | 0.29 ± 0.03 (2) | 2.62 ± 0.02 (29) |
A/ck/VN/NCVD-878/2011 | V149A | 0.16 (3) | 1.33 (5) | 0.13 (1) | NT | |
A/ck/VN/NCVD-776/2011 | H253Y | 0.52 ± 0.24 (9) | 0.20 ± 0.03 (1) | 0.10 ± 0.03 (1) | 0.14 ± 0.01 (1) | |
Median |
NA |
0.06 |
0.26 |
0.13 |
0.09 ± 0.01§ |
|
2.3.2.1 |
A/dk/VN/NCVD-664/2010 | H275Y | 527.26 ± 201.10 (1,353) | 1.11 ± 0.67 (3) | 91.22 ± 44.34 (415) | 1.36 ± 0.72 (6) |
A/dk/VN/NCVD-712/2011 | V424I | 2.01 (5) | 0.52 (2) | 0.26 (1) | NT | |
A/dk/VN/NCVD-714/2011 | V424I | 1.72 (4) | 0.53 (2) | 0.31(1) | NT | |
Median |
NA |
0.41 |
0.32 |
0.2 |
0.23 ± 0.01§ |
|
2.3.4 | A/ck/VN/NCVD-296/2009 | I223T | 10.99 ± 2.38 (7) | 0.86 ± 0.33 (2) | 0.52 ± 0.17 (2) | 0.49 ± 0.24 |
A/ck/VN/NCVD-295/2009 | I223T | 10.37 ± 1.78 (6) | 0.93 ± 0.19 (2) | 0.50 ± 0.13 (2) | 0.53 ± 0.18 | |
A/ck/VN/NCVD-283/2009 | I223T | 11.36 ± 3.43 (7) | 0.77 ± 0.28 (2) | 0.49 ± 0.24 (2) | 0.42 ± 0.16 | |
A/dk/VN/NCVD-462/2010 | G147R | 6.76 ± 0.44 (4) | 1.71 ± 0.48 (3) | 0.45 ± 0.06 (2) | 0.40 ± 0.17 | |
Median |
NA |
1.62 |
0.51 |
0.31 |
0.12 ± 0.02§ |
|
1 |
H5N1 Reference viruses | |||||
A/VN/HN30408/2005, clone | H275Y | 155.18 ± 5.77 (1,552) | 0.63 ± 0.12 (1) | 10.88 (64) | 1.13 (6) | |
A/VN/HN30408/2005, clone | N295S | 2.99 ± 0.21 (30) | 0.73 (2) | 0.13 (1) | 0.52 (3) | |
A/Vietnam/1203/2004 |
NA |
0.10 ± 0.02 (1) |
0.46 ± 0.06 |
0.17 ± 0.03 |
0.18 ± 0.03 |
|
NA | H1N1pdm09 Reference viruses | |||||
A/North Carolina/39/2009 | H275Y | 138.06 ± 26.02 (727) | 0.19 ± 0.03 (1) | 16.77 ± 4.47 (335) | 0.26 ± 0.05 (1) | |
A/California/07/2009 | 0.19 ± 0.05 (1) | 0.18 ± 0.02 | 0.05 ± 0.01 | 0.17 ± 0.04 |
* IC 50, 50% inhibitory concentration; NT, not tested; NA, not applicable.
†Compared with the neuraminidase gene sequence of the closest match. (See Table 1 for median IC50 for each clade.)
‡Fold increase compared with the median IC50 of the same clade virus.
§Fold increase compared with the IC50 of the closest matching virus in the same clade. Global Initiative on Sharing All Influenza Data NA accession no. shown in Technical Appendix 1.