Table 1.
Characteristics of adults with acute febrile illness presenting at the Singapore polyclinics between December 2007 and February 2013
| Characteristics (N = 2046) | n (%) | Median illness duration in days (IQR) | P value * |
|---|---|---|---|
| Age groups (years) | |||
| 17–24 | 540 (26.4) | 5 (3–7) | 0.0002 |
| 25–34 | 567 (27.7) | 5 (3–7) | |
| 35–44 | 333 (16.3) | 5 (4–7) | |
| 45–54 | 295 (14.4) | 5 (3–7) | |
| 55–64 | 210 (10.3) | 5.5 (4–7) | |
| 65 and above | 101 (4.9) | 6 (4–8) | |
| Gender | |||
| Female | 725 (35.4) | 5 (4–7) | 0.0001 |
| Male | 1321 (64.6) | 5 (3–7) | |
| Ethnicity | |||
| Chinese | 1083 (51.0) | 5 (4–7) | 0.0011 |
| Indian | 360 (16.9) | 5 (3–7) | |
| Malay | 377 (17.7) | 5 (3–7) | |
| Other | 303 (14.3) | 5 (4–7) | |
| Missing value | 1 (0.0) | ||
| Body mass index | |||
| < 18.5 | 178 (8.7) | 5 (3–7) | 0.6460 |
| 18.5–22.9 | 885 (43.3) | 5 (3–7) | |
| 23 – 27.4 | 682 (33.3) | 5 (3–7) | |
| ≥ 27.5 | 301 (14.7) | 5 (4–7) | |
| Migration status | |||
| Singaporean | 1286 (62.9) | 5 (4–7) | 0.0002 |
| Immigrant | 100 (4.9) | 5 (3–7) | |
| Missing value | 3 (0.1) | ||
| Type of employment | |||
| Blue-collar | 1086 (53.1) | 5 (3–7) | 0.0001 |
| White-collar | 457 (22.3) | 5 (3–7) | |
| Other | 54 (2.6) | 6.5 (4–10) | |
| Unemployed | 447 (21.8) | 5 (4–7) | |
| Missing value | 2 (0.1) | ||
| Housing type | |||
| Condominium | 81 (3.8) | 5 (4–7) | 0.0001 |
| Dormitory/Hostel | 231 (10.9) | 4 (3–6) | |
| HDB Flat | 1588 (74.8) | 5 (3–7) | |
| Landed Property | 135 (6.4) | 5 (4–7) | |
| Work site | 87 (4.1) | 5 (4–7) | |
| Missing value | 2 (0.1) | ||
| Hospitalization as a result of AFI | |||
| No | 1986 (97.1) | 5 (3–7) | 0.0001 |
| Yes | 60 (2.9) | 10 (7–13) | |
| Diabetes | |||
| No | 1952 (95.4) | 5 (3–7) | 0.0301 |
| Yes | 94 (4.6) | 6 (4–8) | |
| Temperature at initial consultation (°C) | |||
| < 38 | 660 (32.3) | 4 (3–7) | 0.0002 |
| 38–38.9 | 999 (48.9) | 5 (4–7) | |
| ≥ 39 | 384 (18.8) | 5 (4–7) | |
| Missing value | 3 (0.2) | ||
| WBC count at initial consultation (103 cells/μL) | |||
| < 4 (Low) | 213 (10.4) | 7 (4–10) | |
| 4–11 (Normal) | 1475 (72.1) | 5 (3–7) | 0.0001 |
| > 11 (High) | 345 (16.9) | 4 (3–7) | |
| Missing value | 13 (0.6) | ||
| Number of symptoms at initial consultation (excluding fever) | |||
| 0–2 | 290 (14.2) | 4 (3–6) | 0.0001 |
| 3–4 | 515 (25.2) | 5 (3–7) | |
| 5–7 | 753 (36.8) | 5 (4–7) | |
| 8 and more | 488 (23.9) | 6 (4–7) | |
| Severity of anemia at initial consultationa | |||
| No anemia | 1821 (89.0) | 5 (3–7) | 0.2473 |
| Mild | 133 (6.5) | 5 (4–7) | |
| Moderate | 54 (2.6) | 5 (4–7) | |
| Severe | 12 (0.6) | 6 (4.5–10) | |
| Missing value | 26 (1.3) | ||
| Influenza-like illnessb | |||
| No | 1371 (67.0) | 5 (3–7) | 0.0001 |
| Yes | 672 (32.8) | 5 (4–7) | |
| Missing value | 3 (0.1) | ||
| Analgesic use | |||
| No | 1060 (51.8) | 4 (3–7) | 0.0001 |
| Yes | 753 (36.8) | 6 (4–7) | |
| Missing value | 233 (11.4) | ||
| Cough medicine use | |||
| No | 1213 (59.3) | 4 (3–7) | 0.0001 |
| Yes | 600 (29.3) | 6 (4–7) | |
| Missing value | 233 (11.4) | ||
| Antibiotic use | |||
| No | 1510 (73.8) | 5 (3–7) | 0.0001 |
| Yes | 303 (14.8) | 6 (4–8) | |
| Missing value | 233 (11.4) | ||
AFI Acute febrile illness, HDB Housing Development Board, IQR Inter-quartile range
a No anaemia (male, ≥ 13; female, ≥ 12); Mild anaemia (male, 11–12.9; female, 11–11.9); Moderate anaemia (8–10.9); Severe anaemia (<8) in Hb (g/dl) [26]
bILI: combination of symptoms including fever, cough, sore throat
* Kruskal-Wallis rank test p value