TABLE 2 

ZIKV NS1-based ELISA performance in prospectively collected specimensa

SubpopulationNo. of specimens within subpopulationsNo. of specimens tested by PRNT (%)ELISA resultNo. of specimens with the following PRNT result:% specimens with divergent ELISA/PRNT resultsSensitivity (95% CI)Specificity (95% CI)PPV (95% CI)NPV (95% CI)
+
MC pregnancies1915 (78.4)+14001 (0.76−1)1 (0.25−1)1 (0.76−1)1 (0.25−1)
010
Non-MC pregnancies257171 (66.5)+1052112.30.92* (0.85−0.96)0.63* (0.49−0.75)0.83* (0.76−0.89)0.80* (0.65−0.90)
9365.3
HIV patients26361 (23.2)+2669.80.83* (0.66−0.95)0.80* (0.63−0.92)0.81* (0.65−0.93)0.83* (0.64−0.94)
5248.2
Tuberculosis patients5520 (36.4)+14001* (0.76−1)1* (0.54−1)1* (0.76−1)1* (0.54−1)
060
University employees3932 (82.1)+1213.10.86* (0.57−0.98)0.94* (0.73−0.99)0.92* (0.64−0.99)0.89* (0.67−0.99)
2176.3
Total specimens633299 (47.2)+171289.40.91* (0.86−0.95)0.75* (0.66−0.83)0.86* (0.80−0.91)0.84* (0.75−0.90)
16845.4
  • a The positive (+) and negative (−) ELISA and plaque reduction neutralization test (PRNT) results are shown. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), and adjusted Wald confidence intervals (95% CI) are shown; values with an P value of <0.0001 are indicated by an asterisk. MC, microcephaly.