Table 1.

Univariable analysis of household-level putative risk factors for Lumpy Skin Disease in Nakuru County, Kenya.

Variable	Category	Cases (n)	%c	Control (n)	%d	OR	95% CI		P-value
Breed	Exotic	29	71	102	62	15.01	2.09	108.04	0.01
	Indigenous	10	24	59	36	Reference	–	–	–
	Mixed	2	5	3	2	15.50	0.03	1.39	172.83
Cattle herd size (categorical)	Small (1–3)	11	27	61	37	Reference	–	–	–
	Medium (4–9)	15	37	67	41	1.76	0.67	4.64	0.25
	Large (≥10)	15	37	36	22	3.51	1.14	10.83	0.03
Cattle herd size (continuous)		41	20	164	80	1.05	1.01	1.09	0.02
Dipping system	Home spraying	37	90	155	97	Reference	–	–	–
	Community dip	4	10	5	3	3.71	0.80	17.29	0.01
Breeding system	AI or own bulla	24	59	97	60	Reference	–	–	–
	Shared bull	17	42	66	41	1.11	0.40	2.36	0.84
LSD vaccinationb	Yes	5	12	15	9	1.52	0.49	4.71	0.47
	No	36	88	149	91	Reference	–	–	–
Replacement cattle	From own herd	30	73	157	96	Reference
	From outside	11	27	7	4	8.38	2.93	23.92	<0.01
Watering system	In rivers	11	27	29	18	3.40	0.83	13.84	0.09
	Communal dams	4	10	38	23	1.25	0.34	4.55	0.74
	Communal boreholes	0	0	1	1	1.00	–	–	–
	Piped and harvested water	26	63	96	59	Reference	–	–	–
Grazing system	Tethering	1	2	9	56	Reference	–	–	–
	Zero-grazing	30	73	118	72	2.60	0.31	21.94	0.38
	Free-range	10	24	37	23	2.88	0.31	26.74	0.35

Odds ratios estimated using logistic regression. Reference categories are based on the largest category size except for “herd size” where the reference is the smallest farm size (1–3 cattle). AI, Artificial insemination; OR, odds ratio; CI, confidence interval.

^aAI and own bull was combined as only 2.4% (4/164) of the control farms used own bull.

^bLSD vaccination between January 2016 and October 2017.

^cCalculation of the cases percentage = number of observations in that variable level divided by the total number of cases, which was 41.

^dCalculation of the controls percentage = number of observations in that variable level divided by the total number of controls, which was 164.