Table 2. MERS-CoV surveillance test result in camels based on sampling site, age and sex, Egypt, August 2015–January 2016 (n = 1,078 camels^a).

Category	Microneutralisation test			CMLE ORb (95% CI)	P value (for odd ratio)	P value (for hypothesis)	rRT-PCR			P value (for hypothesis)
	Number tested	Number positive	Per cent positive				Number tested	Number positive	Per cent positive
Sampling site
Live animal market	289	273	94.5%	5.52 (3.20–9.96)	< 0.0001	p < 0.001 χ2 = 67.47	290	9	3.1%	p < 0.001 χ2 = 31.97
Village/Egypt	339	256	75.8%	1.00	Ref.		340	2	0.6%
Quarantine	164	157	95.7%	7.25 (3.42–17.42)	< 0.0001		164	4	2.4%
Slaughterhouse	239	184	77%	1.09 (0.73–1.61)	0.69		284	26	9.2%
Total	1,031	871	84.5%	NA	NA	NA	1,078	41	3.8%	NA
Age
Young	81	42	51.8%	1.00	Ref.	p < 0.001 χ2 = 71.39	82	2	2.4%	p = 0.77 χ2 = 0.53
Adult	950	829	87.3%	6.34 (3.93–10.24)	< 0.0001		996	39	3.9%
Sex
Male	765	651	85.1%	1.19 (0.82–1.73)	0.35	p = 0.38 χ2 = 0.86	798	21	2.6%	p < 0.001 χ2 = 13.07
Female	266	220	82.7%	1.00	Ref.		280	20	7.1%

CI: confidence interval; CMLE: conditional maximum likelihood estimate; MERS-CoV: Middle East respiratory syndrome coronavirus; NA: not applicable; OR: odds ratio; ref.: reference; rtRT-PCR: real-time reverse transcription PCR.

^a Of 1,078 camels, a subset of 1,031 underwent serum sampling for MERS-CoV antibodies by microneutralisation assays, while all were sampled for rtRT-PCR testing.

^b CMLE OR: Conditional maximum likelihood estimate OR based on Mid-P exact confidence interval.