Table 1.
Hemagglutination inhibition assay comparison between sheep potency reference antisera and post‐infection ferret antisera
| Antigen* | Potency reference antisera (sheep hyperimmune) | Post‐infection antisera (ferret) | ||||||
|---|---|---|---|---|---|---|---|---|
| A/Viet | A/Indo | A/bhg | Control Sheep† | A/Viet | A/Indo | A/bhg | Control Ferret‡ | |
| A/Viet virus (Clade 1) | 40 | 160 | 80 | 10 | 40 | 20 | 10 | 10 |
| A/Viet Ref. antigen (Clade 1) | 160 | 320 | 320 | 80 | 40 | 20 | 10 | 10 |
| A/Indo virus (Clade 2·1) | 40 | 640 | 160 | 10 | 10 | 640 | 10 | 10 |
| A/Indo Ref. antigen (Clade 2·1) | 160 | 2560 | 320 | 160 | 10 | 640 | 10 | 10 |
| A/bhg virus (Clade 2·2) | 80 | 320 | 640 | 10 | 10 | 160 | 160 | 10 |
| A/bhg Ref. antigen (Clade 2·2) | 40 | 320 | 320 | 40 | 10 | 160 | 160 | 10 |
| Control virus§ | 40 | 160 | 160 | 2560 | 10 | 10 | 10 | 320 |
| Control Ref. antigen§ | 80 | 640 | 640 | 2560 | 10 | 10 | 10 | 160 |
*Assay antigen was either (1) infectious virus or (2) inactivated virus (reference antigen). Homologous titers are indicated in bold.
†A/California/07/2009.
‡New Caledonia/20/1999.
§Control virus and reference antigen were matched to the corresponding control sheep antiserum (A/California/07/2009) and ferret antiserum (New Caledonia/20/1999).