Table 1 Sample characteristics, clinical and parasitological results for all surveyed islands by year [%, (n)]

Gender

Female

52.8 (122)

53.9 (152)

0.859

51.0 (200)

0.752

Median age (IQR^c)

16 (7–27)

12 (6–26)

0.653

14 (8–25)

0.877

Age group in years

0–5

17.7 (41)

23.0 (62)

0.268

15.8 (62)

0.120

6–10

22.5 (52)

20.2 (57)

0.588

18.9 (74)

0.552

11–20

24.2 (56)

19.5 (55)

0.198

35.7 (140)

< 0.001

> 20

35.5 (82)

38.3 (108)

0.522

29.6 (116)

0.051

Fever (> 37.5 °C)

8.2 (19)

0.0 (0)

< 0.001

8.2 (32)

< 0.001

Enlarged spleen (< 12 years old)

69.8 (74/106)

28.8 (23/80)

< 0.001

2.9 (2/70)

< 0.001

Parasite prevalence

19.0 (44)

3.2 (9)

< 0.001

0 (0)

< 0.001

Species-specific prevalence

P. falciparum

11.7 (27)

1.8 (5)

< 0.001

0 (0)

< 0.001

P. vivax

6.5 (15)

1.4 (4)

0.004

0 (0)

< 0.001

P. malariae

0.9 (2)

0.0 (0)

0.204

0 (0)

0.054

Gametocyte prevalence^d

P. falciparum

7.8 (18)

0.7 (2)

< 0.001

0 (0)

< 0.001