Table 1 Baseline characteristics at admission to the ICU

Demographics

Age (years; mean ± SD)

38.4 ± 11.1

37.1 ± 10.2

42 ± 12.8

0.049

   Male sex (n [%])

88 (72.1)

62 (70.5)

26 (76.5)

0.506

   Return from Sub-Saharan Africa (n [%])

107 (87.7)

76 (86,4)

31 (91.2)

0.350

   Nonimmune patients (n [%])

88 (72.1)

62 (70.5)

26 (76.5)

0.506

   Compliant chemoprophylaxis users (n [%])

24 (19.7)

17 (19.3)

7 (20.6)

0.874

   Latency period (arrival-admission; days; median [IQR])

10 (6–15)

10 (7–15)

8 (4–14)

0.778

Initial signs and symptoms

   Fever (>37°C; n [%])

118 (96.7)

84 (95.5)

34 (100)

0.265

   Headache (n [%])

71 (58.2)

57 (64.8)

14 (41.2)

0.018

   Chills (n [%])

43 (35.2)

31 (35.2)

12 (35.3)

0.994

   Diarrhoea (n [%])

46 (37.7)

29 (33)

17 (50)

0.082

   Nausea (n [%])

47 (38.5)

31 (35.2)

16 (47.1)

0.229

   Vomiting (n [%])

29 (23.8)

20 (22.7)

9 (26.5)

0.687

   Jaundice (n [%])

11 (9)

0 (0)

11 (32.4)

0.000

   Confusion (n [%])

5 (4.1)

0 (0)

5 (14.7)

0.001

   Vertigo (n [%])

25 (20.5)

14 (15.9)

11 (32.4)

0.044

   Myalgias (n [%])

47 (38.5)

34 (38.6)

13 (38.2)

0.967

   Abdominal pain (n [%])

10 (8.2)

6 (6.8)

4 (11.8)

0.893

Simplified Acute Physiology Score II (median [IQR])

13 (9–20)

13 (9–17)

27 (17–36)

0.000

IMC/ICU length of stay (days; median [IQR])

5 (3–6)

4 (2–5)

6 (5–8)

0.000

Hospital length of stay (days; median [IQR])

6 (5–8)

5.5 (4–7)

8 (7–10)

0.000