Table 4.
Characteristic features associated with different DENV serotypes, Nepal
| DENV-1 (N = 58) | DENV-2 (N = 25) | DENV-3 (N = 2) | DENV-4 (N = 5) | P value | ||
|---|---|---|---|---|---|---|
| Age in years, median (IQR) | – | 29.0 (17.8–40.0) | 28.0 (15.5–36.0) | ND | 25.0 (20.0–37.5) | 0.696 |
| Age group (years) | ≤ 15 | 9 (15.5) | 6, 24.0 | 0 | 0 | 0.489 |
| > 15 | 49 (84.5) | 19 (76.0) | 2 (100.0) | 5 (100.0) | ||
| DOI median (IQR)* | – | 3.0 (2.0–4.0) | 4.0 (3.0–5.0) | ND | 6.0 (4.0–6.0) | 0.01 |
| Sex | Male | 41 (70.7) | 15 (60.0) | 2 (100.0) | 3 (60.0) | 0.571 |
| Outbreak site | Western | 7 (12.1) | 15 (60.0) | 0 | 0 | < 0.001 |
| Central | 51 (87.9) | 10 (40.0) | 2 (100.0) | 5 (100.0) | ||
| Immune response† | Primary | 38 (65.5) | 7 (28.0) | 2 (100.0) | 1 (20.0) | 0.014 |
| Secondary | 20 (34.5) | 18 (72.0) | 0 | 4 (80.0) | ||
| Disease spectrum | DF | 52 (89.7) | 16 (64.0) | 2 (100.0) | 5 (100.0) | 0.01 |
| DHF/DSS | 6 (10.3) | 9 (36.0) | 0 | 0 |
DENV = dengue virus; DF = dengue fever; DHF = dengue hemorrhagic fever; DOI = days postonset of illness; DSS = dengue shock syndrome; IQR = interquartile range; ND = not done. P value was calculated for age and DOI by Kruskal–Wallis test in three groups (DENV-1, -2, and -4).
DOI difference between two groups was estimated by Mann–Whitney U test for DENV-1 vs. -2 (P = 0.023), DENV-1 vs. -4 (P = 0.007) and DENV-2 vs. -4 (P = 0.112). For categorical variables, difference was calculated using χ2 test. DENV-3 was not included in the statistical analysis due to small sample size (N = 2). Figures in the parenthesis indicate percentages unless otherwise indicated.
Secondary infection was more common with DENV-2 compared with DENV-1 (P = 0.002).