Swine influenza virus infection in different age groups of pigs in farrow-to-finish farms in Thailand

Table 4 Number of seropositive pigs against H3 swine influenza viruses by commercial H3N2 Swine influenza virus ELISA test and HI test in different farms and different age groups

Farm	Groups	Jun.-Jul.2008				Oct.-Nov.2008				Jan.2009				Jul. 2009				Nov. 2009
		ELISA^a	HI^b		n ^c	ELISA	HI		n	ELISA	HI		n	ELISA	HI		n	ELISA	HI		n
			Ha	Hb			Ha	Hb			Ha	Hb			Ha	Hb			Ha	Hb
B	Sow	8	5	0	10	6	4	0	10	8	6	0	10	5	4	0	10	5	3	0	10
	Fattening pig	- ^d				5	6	0	10	6	3	0	10	10	7	0	10	0	0	0	10
	Weaned pig	0	5	0	20 ^e	2	1	0	10	0	1	0	10	2	0	0	10	0	0	0	10
	Introduced pig	-				-				-				1	3	0	10 ^e	0	0	0	10
C	Sow	5	0	4	10	1	0	4	10	2	0	3	10	1	0	1	10	3	0	0	10
	Fattening pig	0	0	0	10	0	0	0	10	0	0	0	10	0	0	0	10	0	0	0	10
	Weaned pig	0	0	0	10	0	0	0	10	0	0	0	10	0	0	0	10	0	0	0	10
	Introduced pig	-				-				-				0	0	0	10	0	0	0	11
D	Sow	-				0	0	0	10	2	0	0	10	0	0	0	10	1	0	0	10
	Fattening pig					0	0	0	10	0	0	0	10	0	0	0	10	0	0	0	10
	Weaned pig					0	0	0	10	0	0	0	10	0	0	0	10	0	0	0	10
E	Sow	10	10	0	10	10	9	0	10	8	8	0	8	-				-
	Fattening pig	0	0	0	10	2	0	0	10	0	0	0	10
	Weaned pig	0	0	0	10	3	0	0	10	2	0	0	10
	Introduced pig	-				-				0	0	0	3
F	Sow	-				1	0	0	10	1	1	0	10	1	1	0	9	-
	Fattening pig					0	0	0	10	0	0	0	10	0	0	0	10
	Weaned pig					1	0	0	10	0	0	0	10	0	0	0	10

^aSample to positve (S/P) ratios were calculated using the optical density (OD) of each sample, positive control and negative control. The S/P rations greater than 0.40 were considered as positive for antibodies against H3N2 SIVs
^bSamples showing HI activity at 1:40 or higher were considered as positive against antigens A/swine/Saraburi107725-28/2008 (H3N2) (Ha) and A/swine/Chachoengsao/2003 (H3N2) (Hb)
^cNumber of serums collected
^dSamples were not collected
^eThe groups from which H3N2 SIVs were isolated

ISSN: 1743-422X