|
Parasite density
|
Cases†
|
Controls‡
| | | |
|---|
|
(/μL)
|
n
|
%¥
|
n
|
%¥
|
aOR
|
AF
|
PAF
|
|---|
|
0
|
666
|
78
|
760
|
84
|
1
| | |
|
1-400
|
99
|
12
|
88
|
10
|
1.1
|
0.06
| |
|
401-4000
|
50
|
6
|
47
|
5
|
0.7
|
0£
| |
|
4001-40000
|
26
|
3
|
12
|
1
|
1.3
|
0.24
| |
|
40000+
|
11
|
1
|
1
|
0
|
7.0
|
0.86
| |
|
Total
|
852
| |
908
| | |
0.11
|
0.02
|
- † Cases: with fever, axillary temperature ≥ 37.5°C at hospital visit.
- ‡ Controls: without fever, axillary temperature < 37.5°C at hospital visit and no reported history of fever during the preceding 3 days.
- ¥ Percentage of patients in a certain parasite density class among cases/controls. aOR: odds-ratio (of fever at each stratum of parasite density, versus uninfected patients), adjusted for age; AF: attributable fraction, calculated as:
;
- £ (AF by definition ≥ 0)
- PrevMal = % febrile patients with malaria infection
- PAF: population attributable fraction, calculated as: PAF = AF(PrevMal).
;