Table 2. Sensitivity and specificity results for validation set in blinded evalution for study of Zika diagnosis, Singapore*.
| Phase | Sensitivity, % (95% CI) |
Specificity, % (95% CI) |
|||||
|---|---|---|---|---|---|---|---|
| ELISA | Lateral flow |
ELISA | Lateral flow |
||||
| F1 | F2 | F1 | F2 | ||||
| Acute, 1–6 dpo | |||||||
| IgM | 41.4 (29.8–53.8) | 51.4 (39.2–63.6) | 50.0 (37.8–62.2) | 100.0 (95.5–100.0) | 95.1 (87.8–98.6) | 97.5 (0.91–1.00) | |
| IgG | 22.9 (13.7–34.4) | 44.3 (32.4–56.7) | 20.0 (11.4–31.3) | 98.8 (93.3–100.0) | 92.6 (84.6–97.2) | 98.8 (0.93–1.00) | |
| IgM/IgG | 52.9 (40.6–64.9) | 68.6 (56.4–79.1) | 60.0 (47.6–71.5) | 98.8 (93.3–100.0) | 88.9 (80.0–94.8) | 96.3 (0.90–0.99) | |
| NS1 | 41.4 (29.8–53.8) | NP | NP | 97.5 (91.4–99.7) | NP | NP | |
| IgM/NS1 | 55.7 (43.3–67.6) | NP | NP | 97.5 (91.4–99.7) | NP | NP | |
| IgG/NS1 | 61.4 (49.0–72.8) | NP | NP | 96.3 (89.6–99.2) | NP | NP | |
| IgM/IgG/NS1 |
67.1 (54.9–77.9) |
NP |
NP |
|
96.3 (89.6–99.2) |
NP |
NP |
| Convalescent, 7–21 dpo | |||||||
| IgM | 79.2 (65.0–89.5) | 70.8 (55.9–83.0) | 70.8 (55.9–83.0) | 95.7 (88.0–99.1) | 87.1 (77.0–93.9) | 94.3 (86.0–98.4) | |
| IgG | 83.3 (69.8–92.5) | 89.6 (77.3–96.5) | 79.2 (65.0–89.5) | 84.3 (73.6–91.9) | 78.6 (67.1–87.5) | 90.0 (80.5–95.9) | |
| IgM/IgG | 89.6 (77.3–96.5) | 89.6 (77.3–96.5) | 87.5 (74.8–95.3) | 80 (68.7–88.6) | 68.6 (56.4–79.1) | 84.3 (73.6–91.9) | |
*ELISA and IA assays were evaluated for the detection of NS1, IgM, and IgG with TTSH plasma samples (ZIKV: n = 70 with 1–6 dpo, and n = 48 with 7–16 dpo; DENV: n = 81 with 1–6 dpo, and n = 70 with 7–21 dpo. Sensitivity and specificity were determined with positive plasmas divided by the total number of respective ZIKV and DENV plasma samples. DENV, dengue virus; dpo, days postonset of symptoms; F1, capture format; F2, detector format; IA, immunochromatographic assay; NP, not performed (NS1 antigen test was not performed in the lateral flow formats because of low sensitivity); NS1, nonstructural protein 1; ZIKV, Zika virus.