Background
Methods
Ethical approval
Study designs
Clinical data collection
Sample collection
DNA extraction and genotyping
Measurement of immune responses
Antigens
Serum references
ELISA
Determination of malaria status
Data cleaning
Statistical analysis
Results
Epidemiological factors
Study location | Number of participantsa
| Gender (%) | Age (%) | Ethnicityb (%) | Altitude range (m) | Bednet usage (%) | Malaria prevalence (%) | Timings of clinical data collection | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Male | <1 | 1–2 | 2–5 | 5–15 | 15–30 | >30 | NA | Slide-positive | NA | |||||||
Senegal | 497 | 45.7 | 1.8 | 3.4 | 10.7 | 37.6 | 21.5 | 24.9 | – | Wolof: Serer: Peulh: Serer Niominka: Mandigue: Other: | 35.6 33.4 10.7 10.1 6.0 4.2 | 15–51 | – | 14.7 | 85.3c
| LS with ACD; TS; 2006/2007 |
Mali (Pongonon) | 312 | 53.5 | – | 3.2 | 36.2 | 54.5 | 2.2 | 3.8 | – | Dogon: Other: | 95.2 4.8 | 49–352 | – | 100 | – | CS & CES; TS; 2006/2007 |
Mali (Manteourou) | 643 | 43.4 | – | – | 10.6 | 37.6 | 21.5 | 24.9 | – | Dogon: Peulh: | 51.2 48.8 | 267–280 | – | 24.6 | – | CS; TS; 2006/2007 |
Burkina Faso | 1,897 | 43.4 | 2.7 | 3.1 | 13.2 | 34.9 | 23.8 | 22.3 | – | Peulh: Mossi: Rimaibe: Other: | 38.9 32.4 27.4 1.3 | 304–305 | 16.5 | 44.3 | 2.5 | CS; TS & IDS; 2007/2008 |
Sudan | 84 | 36.6 | – | – | – | 44.0 | 34.5 | 20.2 | 1.2 | Hausa: Masalit: | 51.2 48.8 | 183–381 | – | – | 100c
| LS & CS; TS & IDS; 2007/2008 |
Kenya | 1,809 | 52.0 | – | – | – | 100 | – | – | – | Giriama: Chonyi: Kauma: Mjikenda: Other: | 78.3 13.1 5.4 1.3 1.9 | 0 | 90.8 | 16.6 | – | BCS |
Tanzania (Moshi) | 6,084 | 40.7 | 6.2 | 4.8 | 16.8 | 33.9 | 21.2 | 16.7 | 0.4 | Pare: Wasambaa: Chagga: Wabondei: Other: | 40.9 36.1 14.3 7.9 0.8 | 196–1,845 | – | 15.6 | 0.5 | CS; TS; 2006/2007 |
Tanzania (Tanga SP1) | 623 | 43.2 | 0.3 | 2.6 | 25.7 | 63.8 | 7.5 | – | – | Wasambaa: Mzigua: Muha: Other: | 65.8 10.8 3.4 20.0 | 223–700 | 54.6 | 22.6 | – | CS; TS; 2001/2002 |
Tanzania (Tanga SP2) | 552 | 47.5 | 3.4 | 2.0 | 9.2 | 51.6 | 23.7 | 10.0 | – | Wasambaa: Mdigo: Mmakonde: Mzigua: Mseguju: Wabondei: Pare: Other: | 35.0 30.2 5.4 5.1 4.7 4.2 4.2 11.2 | 0–1,009 | 28.6 | 37.7 | – | CS; TS; 2004 |
Sri Lanka | 798 | 49.5 | – | – | – | 0.5 | 37.1 | 62.2 | 0.3 | 99.4 Other: 0.6 | 99.4 0.6 | 55–397 | 95.7 | 0 | – | LS with ACD; 1992/1993; samples collected 2006/2007 |
Factor | Adjusted OR (95 % CI) | p-value | Malaria status by microscopy | |||
---|---|---|---|---|---|---|
Individuals positive (total = 1,966) | Individuals negative (total = 7,261) | |||||
N | (%) | N | (%) | |||
Age (years) | ||||||
<1 | 1 | 37 | (10.9) | 303 | (89.1) | |
1–2 | 1.33 (0.87–2.05) | 0.191 | 47 | (17.2) | 225 | (82.7) |
2–5 |
2.65 (1.88–3.72)
|
<0.001
| 311 | (26.7) | 854 | (73.3) |
5–15 |
3.49 (2.53–4.86)
|
<0.001
| 1,141 | (25.6) | 3,314 | (74.4) |
15–30 | 1.21 (0.87–1.70) | 0.263 | 281 | (17.1) | 1,365 | (82.9) |
>30 |
0.63 (0.44–0.90)
|
0.010
| 147 | (11.1) | 1,177 | (88.9) |
Gender | ||||||
Female | 1 | 1,044 | (20.1) | 4,142 | (79.9) | |
Male | 1.09 (0.98–1.21) | 0.109 | 922 | (22.8) | 3,119 | (77.2) |
HbS | ||||||
11 | 1 | 1,824 | (21.4) | 6,718 | (78.6) | |
12 |
0.75 (0.61–0.92)
|
0.005
| 136 | (21.1) | 508 | (78.9) |
22 | ND | ND | 0 | (0) | 8 | (100) |
Correlations between antibody levels
Factors influencing antibody levels
Factor | Anti-AMA1 levels (n = 10,137) | Anti-MSP1 levels (n = 10,200) | Anti-MSP2 levels (n = 10,283) | Anti-NANP levels (n = 5,531)a
| Total IgE levels (n = 4,961)a
| |||||
---|---|---|---|---|---|---|---|---|---|---|
Beta (95 % CI) | p-value | Beta (95 % CI) | p-value | Beta (95 % CI) | p-value | Beta (95 % CI) | p-value | Beta (95 % CI) | p-value | |
Age (years) | ||||||||||
<1 | 0 | 0 | 0 | 0 | 0 | |||||
1–2 | 0.04 (−0.09 to 0.17) | 0.576 | −0.10 (−0.22 to 0.01) | 0.083 |
0.16 (0.05 to 0.28)
|
0.006
|
0.30 (0.04 to 0.55)
|
0.023
| 0.09 (−0.17 to 0.35) | 0.508 |
2–5 |
0.25 (0.15 to 0.35)
|
<0.001
| 0.08 (−0.01 to 0.17) | 0.087 |
0.29 (0.20 to 0.38)
|
<0.001
|
0.50 (0.30 to 0.71)
|
<0.001
| 0.09 (−0.12 to 0.30) | 0.398 |
5–15 |
0.57 (0.47 to 0.67)
|
<0.001
|
0.37 (0.28 to 0.45)
|
<0.001
|
0.61 (0.52 to 0.69)
|
<0.001
|
0.87 (0.67 to 1.07)
|
<0.001
| 0.19 (−0.01 to 0.40) | 0.066 |
15–30 |
0.55 (0.46 to 0.65)
|
<0.001
|
0.65 (0.57 to 0.74)
|
<0.001
|
0.72 (0.63 to 0.81)
|
<0.001
|
1.43 (1.23 to 1.63)
|
<0.001
|
0.22 (0.02 to 0.43)
|
0.034
|
>30 |
0.53 (0.43 to 0.63)
|
<0.001
|
0.81 (0.72 to 0.90)
|
<0.001
|
0.72 (0.63 to 0.81)
|
<0.001
|
1.61 (1.40 to 1.81)
|
<0.001
| 0.14 (−0.07 to 0.35) | 0.179 |
Gender | ||||||||||
Female | 0 | 0 | 0 | 0 | 0 | |||||
Male | −0.03 (−0.07 to 0) | 0.058 |
−0.08 (−0.11 to −0.05)
|
<0.001
|
−0.05 (−0.07 to −0.02)
|
0.002
|
−0.07 (−0.11 to −0.03)
|
0.004
|
0.12 (0.09 to 0.16)
|
<0.001
|
Microscopy result | ||||||||||
Negative | 0 | 0 | 0 | 0 | 0 | |||||
Positive |
0.17 (0.13 to 0.22)
|
<0.001
|
0.15 (0.11 to 0.19)
|
<0.001
|
0.21 (0.18 to 0.25)
|
<0.001
| −0.03 (−0.08 to −0.02) | 0.263 |
0.06 (0.01 to 0.11)
|
0.021
|