TABLE 1.
Analysis of serial passages of two strains of H3N8 by hemagglutination assay and RT-PCR/sequencing
| Strain | Passage no. | Hemagglutination assay titera | Amino acid at position 190b |
|---|---|---|---|
| BOL/96 | 2 | <4 | −c |
| 3 | 8 | K | |
| 4 | 64 | Q | |
| 5 | 128 | Q | |
| ALV/96 | 2 | <4 | −c |
| 3 | 16 | K | |
| 4 | 126 | Q | |
| 5 | 256 | Q |
a
Hemagglutinating assay titer is expressed as the reciprocal of the highest dilution of allantoic fluid agglutinating an equal volume of 1% chick erythrocytes.
b
Deduced amino acid at position 190 of the virus HA, determined by sequencing of amplification products.
c
−, no amplification product detected.