Table 3. Results showing the seroprevalence estimates of C. burnetii in humans based on analysis performed using combined data for all animals from both counties and subset data from Tana River county.

Variable	Category	Combined data from both counties			Tana River county
		n	% Seroprevalence (95% CI)	P-value	n	% Seroprevalence (95% CI)	P-value
Gender	Male	382	28.27 (23.81–33.08)	0.03	180	26.11 (19.86–33.17)	0.74
	Female	590	22.03 (18.75–25.60)		303	24.75 (20.00–30.01)
Occupation	Pastoralist	246	26.42 (21.02–32.40)	0.32	145	26.90 (19.88–34.89)	0.53
	Mixed crop-livestock farmer	170	25.29 (18.95–32.52)		35	17.14 (6.56–33.65)
	Student	114	29.82 (21.62–39.11)		29	31.03 (15.28–50.83)
	Other*	73	17.81 (9.93–28.53)		50	22.00 (11.53–35.96)
Age	≤17	339	27.14 (22.48–32.21)	0.30	177	27.68 (21.24–34.90)	0.41
	18–40	375	22.13 (18.03–26.68)		191	22.00 (16.33–28.54)
	>40	258	24.42 (19.31–30.13)		115	26.96 (19.11–36.03)
Location	Ijara	253	18.97 (14.33–24.36)	0.09
	Sangailu	237	28.69 (23.02–34.90)
	Bura	262	24.81 (19.70–30.50)		262	24.81 (19.70–30.50)	0.83
	Hola	222	25.68 (20.06–31.95)		222	25.68 (20.06–31.95)
Own livestock	No	33	30.30 (15.59–48.71)	0.47	14	35.71 (12.76–64.86)	0.36
	Yes	691	24.75 (21.57–28.14)		455	24.84 (20.93–29.07)
Land use	Irrigation	268	26.87 (21.65–32.60)	0.54	8	0.00 (0.00–36.94)	0.25
	Pastoralism	628	23.41 (20.15–26.92)		428	25.47 (21.40–29.87)
	Riverine	74	24.32 (15.10–35.69)		48	27.08 (15.28–41.85)
Source of water	Borehole	127	20.47 (13.83–28.54)	0.36	84	15.48 (8.51–25.00)	0.18
	Canal	231	28.14 (22.43–34.41)		231	28.14 (22.44–34.41)
	Dams	336	23.81 (19.36–28.73)		127	24.41 (17.23–32.82)
	Tap	13	30.77 (9.09–61.43)		12	33.33 (9.92–65.11)
	Others e.g., rivers	17	35.29 (14.21–61.57)		15	33.33 (11.82–61.62)
Family size	≤5	212	27.83 (21.91–34.38)	0.13	96	19.79 (12.36–29.17)	0. 13
	6–10	497	25.35 (21.58–29.42)		285	29.12 (23.91–34.77)
	>10	263	20.15 (15.48–25.52)		103	19.42 (12.28–28.38)
Herd exposure	Exposed				181	28.33 (21.88–35.52)	0.19
	unexposed				138	21.58 (15.06–29.35)

n, number of humans tested; CI, confidence interval. Except for location, all the other variables in this table (gender, occupation, age, own livestock, land use, source of water and family size) had missing data. Thus, the totals within their respective categories were not equal to the sampled number of 974 for the combined data or 484 for Tana River county. Herd exposure also had missing data.

*Other occupations included community health workers, businessmen and women, housewives, chiefs, drivers and those employed such as nurses.