Table 5.

JEV blocking ELISA results for determination of antibody titres in pigs at different times after challenge. The titre was determined as the highest 2-fold dilution of the sample that gave a result above the cut-off value (PI = 40%). Positive samples are indicated by shading with the titre shown. negative samples: Neg.

Challenge Method	Age at Challenge	Dose of JEV (TCID50/Pig)	Pig No.	Day 0	Day 3	Day 5	Day 6	Day 7	Day 8	Day 9	Day 10 a	Day 14	Day 19/21	Day 28
Intradermal	5 weeks	1 × 104.5	1	Neg	Neg	40	160	640	1280	1280	320a	640	640	640
			2	Neg	Neg	160	1280	5120	5120	2560	1280	1280	1280	1280
			3	Neg	Neg	320	1280	10,240	10,240	5120	2560	2560	5120	2560
			4	Neg	Neg	80	640	2560	5120	5120	1280	NS	NS	NS
			5	Neg	Neg	320	1280	10,240	5120	5120	5120	640	1280	2560
		1 × 105.5	6	Neg	Neg	320	1280	5120	2560	2560	640	NS	NS	NS
			7	Neg	Neg	20	160	1280	2560	2560	640	640	640	1280
			8	Neg	Neg	160	1280	5120	5120	2560	1280	NS	NS	NS
			9	Neg	Neg	320	1280	10,240	5120	5120	1280	2560	2560	5120
	11 weeks	1 × 105.0	10	Neg	Neg	160	640	2560	NS	2560	1280	640	1280	NS
			11	Neg	Neg	20	80	640	NS	2560	1280	320	1280	NS
			12	Neg	Neg	80	320	1280	NS	1280	640	320	640	NS
			13	Neg	Neg	80	320	1280	NS	1280	640	160	320	NS
			14	Neg	Neg	80	320	1280	NS	1280	1280	320	640	NS
			15	Neg	10	40	40	320	NS	1280	1280	640	320	NS
			16	Neg	Neg	160	640	10,240	NS	10,240	640	640	1280	NS
			17	Neg	Neg	80	320	1280	NS	1280	1280	320	640	NS
			18	Neg	Neg	21	80	640	NS	1280	640	320	640	NS
Intranasal	5 weeks	1 × 104.5	19	Neg	Neg	Neg	Neg	10	80	640	2560	NS	NS	NS
			20	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg
			21	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg
			22	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	NS	Neg	Neg
			23	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg
		1 × 105.5	24	Neg	Neg	Neg	Neg	Neg	Neg	40	1280	NS	NS	NS
			25	Neg	Neg	Neg	160	2560	5120	5120	10,240	NS	NS	NS
			26	Neg	Neg	Neg	Neg	Neg	10	40	1280	5120	1280	5120
			27	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg	Neg

^a Plasma from EDTA blood was used on Day 10; some pigs were euthanized on Day 10 and have no further samples (NS).