Seroprevalence and epidemiological risk factors for Kasba virus among sheep and goats in South Korea: a nationwide retrospective study

Figures & Tables

Province	2003		2004		2005		2006		2007		2008
Province	+	Tested	+	Tested	+	Tested	+	Tested	+	Tested	+	Tested
Gyeonggi	7	159	14	124	9	73	5	79	13	129	8	148
Gangwon	10	130	9	79	8	129	2	95	8	55	3	87
Chungbuk	8	83	15	84	8	94	5	114	9	126	2	120
Chungnam	6	57	10	86	3	51	9	120	5	175	6	88
Jeonbuk	8	79	14	156	3	179	16	81	16	150	10	119
Jeonnam	14	91	15	108	9	135	10	139	24	73	9	108
Gyeongbuk	6	58	12	94	16	103	13	96	9	89	16	89
Gyeongnam	10	94	13	64	19	71	5	94	18	72	6	134
Jeju	19	112	19	90	9	72	9	79	16	79	6	79
Subtotal	88	863	121	885	84	907	74	897	118	948	66	972

			Univariate analysis
Variable	Positive (n=139)	Negative (n=776)	OR (95% CI)	P value	OR (95% CI)	P value
Animal species
Goat	60	450	Reference
Sheep	55	438	0.942 (0.638–1.389)	0.762
Age class
Juvenile	20	242	Reference		0.575 (0.334–0.989)	0.044
Subadult	44	291	1.830	0.031	1.052	0.816
			(1.050–3.188)		(0.683–1.621)
Adult	51	355	1.738 (1.011–2.990)	0.044	Reference
Population sizes of the flocks
<6 head	28	280	Reference		0.707 (0.428–1.166)	0.173
6-10 head	43	297	1.448 (0.875–2.395)	0.148	1.023 (0.653–1.604)	0.920
>10 head	44	311	1.415 (0.858–2.334)	0.173	Reference
Flock structure
Goats and/or sheep alone	66	502	Reference
With other ruminants	49	386	0.966 (0.652–1.430)	0.861
Reproductive problems
No	79	701	Reference
Yes	36	187	1.708 (1.116–2.615)	0.013
Vector control
No	88	591	Reference
Yes	27	297	0.611	0.031
			(0.388–0.961)
Presence of ruminant farms
within a 1-km radius
No	60	461	Reference
Yes	55	427	0.990 (0.671–1.460)	0.958
Presence of lakes or rice paddies within
a 1-km radius
No	63	512	Reference
Yes	52	376	1.124 (0.761–1.661)	0.558
Land use
Urban	15	199	Reference		0.540 (0.297–0.981)	0.041
Agricultural	54	387	2.021 (1.098–3.718)	0.022	Reference
Woodland and seminatural	46	302	1.851 (1.019–3.363)	0.041	1.092 (0.716–1.663)	0.683
Location of the farm
in South Korea
Northern	41	440	Reference
Southern	74	448	1.773 (1.184–2.654)	0.005
Location of the farm in South Korea
Eastern	86	543	Reference
Western	29	345	1.884 (1.211–2.931)	0.004

	Flock-level seroprevalence			Animal-level seroprevalence
Province latitude–longitude	Positive*	Tested	%	Positive*	Tested	%
Incheon (N) 36°55′–37°58′ (E) 124°36′–126°47′	1	10	10.0	2	25	8.0
Ulsan (N) 35°19′–35°43′ (E) 128°58′–129°27′	1	12	8.3	3	27	11.1
Gyeonggi (N) 36°53′–38°17′ (E) 126°22′–127°51′	10	105	9.5	31	281	11.0
Gangwon (N) 38°09′–39°25′ (E) 126°46′–128°22′	1	38	2.6	2	84	2.4
Chungbuk (N) 37°15′–36°00′ (E) 127°16′–128°38′	2	34	5.9	6	91	6.6
Chungnam (N) 35°58′–37°03′ (E) 125°32′–127°38′	1	60	1.7	2	87	2.3
Jeonbuk (N) 35°18′–36°09′ (E) 125°58′–127°54′	3	33	9.1	8	93	8.6
Jeonnam (N) 33°54′–35°30′ (E) 125°04′–127°54′	2	44	4.5	30	105	28.6
Gyeongbuk (N) 35°34′–37°33′ (E) 127°48′–131°52′	2	43	4.7	8	85	9.4
Gyeongnam (N) 34°39′–35°54′ (E) 127°35′–129°28′	3	44	6.8	10	87	11.5
Jeju (N) 33°06′–34°00′ (E) 126°08′–126°58′	2	18	11.1	13	38	34.2
Total (N) 33°06′–39°25′ (E) 124°36′–131°52′	28	441	6.3	115	1003	11.5