Table 3. Immunogenicity of a H7N9 split vaccine prepared from the H7N9/PR8 transfectant virus.

Immunogena	HAI antibody titerb (GMT)
	Mice		Ferrets
H7N9/PR8 spilt vaccine	7.5 µg	80	160
	15 µg	104	190
	30 µg	195	340
	45 µg	320	640
PBS	–	<10	<10

^aGroups of mice and ferrets received two doses of 7.5, 15, 30 or 45 µg monovalent influenza A (H7N9) split vaccine or PBS i.m in 14 days intervals.

^bSerum samples were collected and assayed at 2 weeks after boost.