Table 2.
Clinical and Laboratory Features of the Returning Travelers Diagnosed With Dengue Fever (2000–2006 by Antibody Detection and 2012–2016 by NS1 Antigen RDT) at the Institute of Tropical Medicine, Antwerp, Belgiuma
| Features of Study Participants | “Historical Antibody Detection Group” 2000–2006 (n = 43) |
“Contemporary NS1Antigen Group” 2012–2016 (n = 43) |
P |
|---|---|---|---|
| Epidemiological Data | |||
| Male | 24 (56) | 21 (49) | NS |
| Age group 15–60 years | 42 (98) | 38 (88) | NS |
| Stay in Southern Asia (Southeast Asia and Indian subcontinent) | 33 (77) | 30 (70) | NS |
| Stay in Latin America/Caribbean | 8 (19) | 11 (26) | NS |
| Previous contact with another care provider | 16 (37) | 15 (35) | NS |
| Previous antibiotic treatment | 13 (30) | 6 (14) | NS |
| Presenting Symptoms | |||
| Fever onset before return/arrival | 22 (51) | 17 (40) | NS |
| Duration of fever before initial contact, mean in days (range) | 4.6 (1–10) | 4.1 (1–7) | NS |
| Fever ≥39°C | 23 (54) | 28 (65) | NS |
| Headache and/or myalgia | 41 (95) | 40 (93) | NS |
| Cough | 13 (30) | 11 (26) | NS |
| Vomiting and/or diarrhea | 13 (30) | 17 (40) | NS |
| Skin rash (reported or observed) | 24 (56) | 27 (63) | NS |
| Laboratory Testing | |||
| Hemoglobin level mean in g/dL (standard deviation) | 14.8 (1.3) | 14.2 (2.1) | NS |
| Leukopenia (leukocyte count below 4000/µL) | 24 (56) | 27 (63) | NS |
| Thrombocytopenia (platelet count below 150000/µL) | 25 (59) | 19 (44) | NS |
| At least 1 dengue predictor (rash OR leukopenia OR thrombocytopenia) | 37 (87) | 34 (79) | NS |
| Absence of IgM and IgG in acute-phase serum | 17 (39) | 12 (28) | NS |
| Positive RT-PCR in acute phase serum | — | 36b (84) | — |
| Secondary dengue infection | 7 (16) | 9 (21) | NS |
| Severity Parameters and Outcome | |||
| Severe denguec | 2 (5) | 1 (2) | NS |
| Presence of at least one warning signd | 2 (5) | 2 (5) | NS |
| Immediate admission | 14 (33) | 3 (7) | .006 |
| Empirical antibiotic treatment | 11 (26) | 2 (5) | .014 |
| Total fever duration >7 days | 3 (7) | 5 (12) | NS |
Abbreviations: CI, confidence interval; DENV, dengue virus; Ig, immunoglobulin; NS1, nonstructual 1; NS, not significant; OR, odds ratio; RDT, rapid diagnostic test; RT-PCR, reverse-transcriptase polymerase chain reaction.
All results are expressed to the numbers of available data (%). NS1 antigen RDT denotes nonstructural 1 rapid diagnostic test.
Including the following: DENV-1, n = 16; DENV-2, n = 12; DENV-3, n = 5; and DENV-4, n = 3.
In 2000–2006, dengue shock syndrome/dengue hemorrhagic fever (n = 1) and meningitis (n = 1); in 2012–2016, cerebellitis (n = 1).
In 2000–2006, gum bleeding (n = 2); in 2012–2016, gum bleeding (n = 1) and slight hematemesis (n = 1).