Table 3.
Association between malaria episodes and antibody seroprevalence in 18 months old children
| Antigen tested/parasite isolate | Seropositivesa (%) | No episode (n = 457) | Any episode within 18 months % (n = 144) |
p valueb | Single episode % (n = 119) |
p valueb | Multiple episodes % (n = 25) | p valueb | Unadjusted OR (95% CI) | p valuec | Adjusted OR (95% CI) | p valued |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MSP1 19 kDe | 327 (54.4) | 224 (49.0) | 103 (71.5) | < 0.0001 | 83 (69.8) | < 0.0001 | 20 (80.0) | 0.003 | 2.24 (1.59, 3.17) | < 0.0001 | 2.21 (1.56, 3.12) | < 0.0001 |
| MSP2f | 162 (26.9) | 113 (24.7) | 49 (34.0) | 0.028 | 40 (33.6) | 0.051 | 9 (36.0) | 0.207 | 1.41 (1.02, 1.94) | 0.034 | 1.38 (1.00, 1.90) | 0.049 |
| EBA175g | 69 (11.5) | 50 (10.9) | 19 (13.2) | 0.459 | 13 (10.9) | 0.996 | 6 (24.0) | 0.047 | 1.33 (0.87, 2.05) | 0.182 | 1.31 (0.85, 2.01) | 0.216 |
| Rh2A9h | 151 (25.1) | 108 (23.6) | 43 (29.9) | 0.133 | 34 (28.6) | 0.265 | 9 (36.0) | 0.160 | 1.32 (0.95, 1.83) | 0.095 | 1.30 (0.93,1.80) | 0.117 |
| Schizont | 325 (54.1) | 222 (48.6) | 103 (71.5) | < 0.0001 | 85 (71.4) | < 0.0001 | 18 (72.0) | 0.023 | 2.14 (1.52, 3.00) | < 0.0001 | 2.20 (1.55, 3.13) | < 0.0001 |
| E8Bi | 43 (7.2) | 24 (5.3) | 19 (13.2) | 0.001 | 17 (14.3) | 0.001 | 2 (8.0) | 0.554 | 1.85 (1.15, 2.98) | 0.010 | 1.87 (1.15, 3.04) | 0.011 |
| R29i | 21 (3.5) | 13 (2.8) | 8 (5.6) | 0.122 | 7 (5.9) | 0.107 | 1 (4.0) | 0.738 | 1.55 (0.78, 3.09) | 0.204 | 1.51 (0.75, 3.02) | 0.245 |
| 3D7i | 50 (8.3) | 36 (7.9) | 14 (9.7) | 0.485 | 10 (8.4) | 0.850 | 4 (16.0) | 0.152 | 1.31 (0.80, 2.14) | 0.278 | 1.30 (0.79, 2.14) | 0.291 |
Significant p value in italic format
aSamples defined as antibody positive if levels greater than mean + 3SD of negative controls
bp value compared to children with no episode calculated by Chi squared test
cp-value derived from logistic regression with Odds Ratios (OR) and 95% confidence intervals (CI)
dp-value derived from multivariate logistic regression with Adjusted Odds Ratios (OR) after controlling for duration of gestation, HIV infection, gender of the child, maternal anaemia
eMerozoite surface protein 1
fMerozoite surface protein 2
gErythrocyte binding antigen 175
hReticulocyte binding protein homologue 2A
iVariant surface antigen antibody responses