Table 1.

Hemagglutination inhibition and virus neutralization titers against vaccine viruses (Y10 and LP93) and the challenge virus (CL11) on the day of challenge, Day 0

Group	Horse	HI titer			VN titer
		Antigen			Virus
		Y10	LP93	CL11	Y10	LP93	CL11
Y10	Horse 1	64	64	128	256	256	128
	Horse 2	32	32	64	64	64	64
	Horse 3	32	16	16	128	64	64
	Horse 4	64	32	32	256	128	128
	Horse 5	<8	<8	<8	<8	<8	<8
	GMTa , b	27.9 (45.3)	21.1 (32.0)	27.9 (45.3)	73.5 (152.2)	55.7 (107.6)	48.5 (90.5)
LP93	Horse 6	64	64	64	128	256	16
	Horse 7	32	32	32	64	128	8
	Horse 8	64	64	32	256	256	32
	Horse 9	32	32	16	128	128	8
	Horse 10	16	16	8	64	128	<8
	GMT	36.8	36.8	24.3	111.4	168.9	10.6

^aGeometric mean titer.

^bThe GMTs of the Y10 group excluding Horse 5 are represented in parentheses. Horse 5 was considered a poor vaccine responder (see the text).