Occurrence and Risk Factors of Brucellosis in Commercial Cattle Farms from Selected Districts of the Eastern Coast Zone, Tanzania

Table 1

Animal-level seroprevalence of brucellosis stratified by different factors, determined from 1,052 serum samples collected from 20 commercial dairy cattle farms in the eastern coast zone of Tanzania.

Variable	Levels	No. tested	No. positive	Seroprevalence (%)	95% CI	value
Sex	Male	332	60	18.1	13.9–22.3	<0.001
	Female	720	209	29.0	25.7–32.3
Age	Adult (>1 year)	975	226	23.2	20.5–25.8	<0.001
	Young (<1 year)	77	43	55.8	44.7–66.9
Region	Dar-es-Salaam	160	11	6.9	2.9–10.8	<0.001
	Pwani	530	113	21.3	17.8–24.8
	Tanga	362	145	40.1	34.9–45.1
Location	Rural	422	142	33.7	29.1–38.1	<0.001
	Peri-urban	630	127	20.2	17.0–23.3
Season	Dry	786	133	16.9	14.3–19.5	<0.001
	Wet	266	136	51.1	45.1–57.1
Herd size	Large	442	27	6.1	3.9–8.3	<0.001
	Medium	539	237	43.9	39.8–48.2
	Small	71	5	7.0	0.9–13.1
Contact with wildlife	No	530	156	29.4	18.1–25.2	0.004
	Yes	522	113	21.6	25.5–33