Table 3.
Statistical detection of outliers compared to WHO-AVWG criteria
| Virus type/subtype | NA inhibitor | Outlier type | No. of outliers (n) | IC50, nm (fold change)* | NA inhibition** | Amino acid changes in the NA (No. of outliers)*** |
|---|---|---|---|---|---|---|
| A (H1N1)pdm09 (n = 449) | Oseltamivir | Extreme | 8 | 38-27-294·72 (213–1637) | Highly reduced | H275Y (8) |
| Mild | 4 | 0·49–1·22 (3–6) | Normal | S110F (1); T135N + D292N (1) | ||
| Zanamivir | Mild | 2 | 0·36–1·03 (2–6) | Normal | S110F (1) | |
| A (H3N2) (n = 978) | Oseltamivir | Mild | 27 | 0·23–0·76 (2–7) | Normal | I222T + D151D/N (1) |
| Zanamivir | Extreme | 1 | 23·75 (91) | Reduced | Q136Q/K (1) | |
| Mild | 30 | 0·55–1·28 (2–5) | Normal | D151D/N (1); T148I + D251V (1); T148T/I (1); D151D/N (1); D151D/G + D251V (1) | ||
| A (H3N2)v (n = 156) | Oseltamivir | Extreme | 1 | 5·30 (35) | Reduced | S245N + S247P (1) |
| Zanamivir | Extreme | 1 | 35·74 (70) | Reduced | S245N + S247P (1) | |
| B (n = 343) | Oseltamivir | Mild | 1 | 53·02 (6) | Reduced | A200A/T (1) |
| Mild | 4 | 23·50–32·27 (3–4) | Normal | G70R + T72A (2); K343E (1); K107N + K343E (1) | ||
| Zanamivir | Mild | 1 | 5·11 (5) | Reduced | A200A/T (1) |
*
Compared to median IC50 for drug by virus type/subtype.
**
Based on fold change determined by comparing IC50 of test viruses to the median IC50 by virus type/subtype.
***
Number of outliers with amino acid changes in the NA, based on available sequence information.