Table 3.

Biological characteristics of HK/156 and CK/HK/220 H5N1 isolates

IsolatePFU/ml, CEFPlaque size (mm)HA titer, chicken erythrocytesEgg titer (ELD50)50% Infectious dose, MDCK
+Trypsin−Trypsin
HK/1564.0 × 106 4.7 × 106 1–2128108.8 105.8
CK/HK/2201.0 × 107 8.0 × 106 3–41,024108.8 105.8