Table 2.

Sensitivity of the nucleoprotein (NP), RBD-based, and NP/RBD-based IgG ELISAs at a specificity of 98.3%

		Positive sera (%)
Time post infection	No. of sera	NP	RBD	NP/RBD
> 4 weeks	98	82.7 CI [73.74; 89.60]	92.9 CI [85.89; 97.11]	95.9 CI [89.85; 98.87]
4–10 weeks	48	95.8 CIa [85.70; 99.48]	97.9 CI [88.9; 99.95]	100.0 CI [92.60; 100.00]
6 months	50	70.0 CI [55.39; 82.14]	88.0 CI [75.69; 95.47]	92.0 CI [80.77; 97.78]
p-levelb		0.0008*	0.0585	0.0465*

^aCI: 95% confidence interval

^bComparison of the sensitivity 4–10 weeks versus 6 months post infection by the chi-squared test. Significant p-values are labeled with an asterisk