Environmental determinant of malaria cases among travellers

Malaria Journal

Table 3 Incidence rate of clinical malaria attacks and estimations from univariate analysis for a reasoned selection of weather variables (n = 4 531, except other indication)

	Number of clinical malaria attacks	Number of individuals	Number of person-days under survey	Incidence rate per 1,000 person-month	RR	95% CI	p
Cumulated precipitation
>180 mm of water by month*
<33% duration of stay	94	3665	454 512	2,52	1
≥33% duration of stay	46	866	117 851	4,75	1,69	0,87 - 3,26	0,120
Water balance
> +15 mm of water by month*
<66% duration of stay	83	3447	425 615 146 748	5,93	1
≥66% duration of stay	57	1084	146 748	11,81	1,82	1.05 – 3.16	0,032
Consecutive dry week
number of consecutive dry weeks in month
By week (in continuous)					0,93	0,864 - 1,01	0,085
Evapotranspiration
>150 mm of water by month
<33% duration of stay	120	4062	508 236	2,87	1
≥33% duration of stay	20	469	64 127	3,80	1,31	0,58 - 2,95	0,518
Maximal temperature
>30°C
<66% duration of stay	9	485	64 218	1,71	1
≥66% duration of stay	131	4 046	508 145	3,14	1,53	0,61 - 3,87	0,368
Mean temperature
>25°C
< 66% duration of stay	55	1 196	158 856	4,22	1
≥66% duration of stay	85	3 335	413 507	2,50	0,73	0,419 - 1,28	0,271
Mean temperature
By degree Celsius (in continuous)					0,95	0,79 - 1,15	0,629
Minimal temperature
>20°C
< 33% duration of stay	38	693	93 009	4,97	1
≥33% duration of stay	102	3 838	479 354	2,59	0,56	0,27 - 1,16	0,120
Urban area
<33% duration of stay	57	1 191	157 480	4,41	1
≥33% duration of stay	83	3 340	414 883	2,44	0,50	0,30 - 0,86	0,011

CI = confi dence interval; RR = relative risk; * estimates calculated with 0 months of decay.

ISSN: 1475-2875