Table 1. Virus neutralizing activity of serum antibodies from vaccinated SPF chickens.

			ND50/mlb
			Chicken no.
VRPa	Number of immunizations	Vaccine dose (ffu)	#1	#2	#3	#4	#5
VSV*ΔG	2	2×108	<100	<100	<100	<100	<100
VSV*ΔG(HAH5-HP) (UV-irradiated)	2	-	<100	<100	<100	<100	<100
VSV*ΔG(HAH5-HP)	1	2×108	1350	400	141	283	200
	2	2×108	12800	51200	9050	9050	9050
VSV*ΔG(HAH5-HP)	1	2×107	<100	<100	<100	<100	<100
	2	2×107	283	141	<100	<100	<100
VSV*ΔG(HAH5-HP)	2	2×106	<100	<100	<100	<100	<100

^aSPF chickens were immunized (i.m.) once or twice with the indicated doses of either VSV*ΔG or VSV*ΔG(HA_H5-HP).

^bBlood was collected from vaccinated chickens at 9 weeks of age.

Serum was prepared and inactivated for 30 minutes at 56°C. Virus neutralisation assays were performed with HPAIV A/whooper swan/Mongolia/3/2005 (H5N1).