Table 3.
Comparison of NS1 antigen detection and IgM ELISA for diagnosis of dengue based on the duration between fever onset and sample collection for the dengue patients notified in Surat city, Gujarat, India, 2011–2016
| Duration (days) | IgM | NS1* | Both | Total |
|---|---|---|---|---|
| Probable cases (tested negative) | ||||
| n = 5,817, % | n = 4,263, % | n = 1,409, % | N = 11,489, % | |
| 1–5 | 1,458 (25) | 3,216 (75.4) | 819 (58.1) | 5,493 (47.8) |
| 6–10 | 3,460 (59.5) | 958 (22.5) | 479 (34) | 4,897 (42.6) |
| > 10 | 899 (15.5) | 89 (2.1) | 111 (7.9) | 1,099 (9.6) |
| Laboratory-confirmed cases (tested positive) | ||||
| n = 898, % | n = 893, % | n = 212, % | N = 2003, % | |
| 1–5 | 257 (28.6) | 642 (71.9) | 107 (50.5) | 1,006 (50.2) |
| 6–10 | 530 (59) | 224 (25.1) | 89 (42) | 843 (42.1) |
| > 10 | 111 (12.4) | 27 (3) | 16 (7.5) | 154 (7.7) |
*
The total number of NS1-positive patient may be underestimated because NS1 testing results are available from the year 2013.