TABLE 4.

Serum Nt antibody titers and protective immunity elicited by a single i.m. injection of WN virus DNA vaccine in horses

Sample (day)	Titer
	Vaccinated horse no.				Unvaccinated control horse no.
	5	6	7	8	9	10	14	15
Postvaccination
12	<1:10	<1:10	<1:10	<1:10
14	1:10	<1:10	<1:10	<1:10
16	1:10	<1:10	<1:10	<1:10
18	1:40	<1:10	<1:10	<1:10
20	1:40	<1:10	<1:10	<1:10
22	1:40	<1:10	1:10	<1:10
28	1:40	<1:10	1:20	1:10
31	1:40	1:5	1:20	1:10
37	1:40	1:5	1:20	1:20
Postchallenge
2	1:40	1:5	1:20	1:20	<1:2	<1:2	<1:2	<1:2
4	1:40	1:10	1:20	1:40	<1:2	<1:2	<1:2	<1:2
6	1:40	1:10	1:40	1:40	<1:2	<1:2	<1:2	<1:2
8	1:80	1:20	1:40	1:40	1:80	<1:10	<1:10	<1:10
10	1:80	1:20	1:40	1:80	>1:320	<1:10	<1:10	1:160
12	1:160	1:40	1:80	1:160	>1:320	1:20	1:20	>1:320
14	>1:320	1:40	1:160	1:160	>1:320	1:160	1:10	1:160
Viremia titera range (day)					1.3–2.4 (4)	1.0–1.6 (6)		1.3–2.2 (2)

^aViremia titer was expressed as log₁₀ Vero cell PFU/ml of serum.