Table 2.
Magnitude and prevalence of antibodies and IgG responses in parasitaemic and aparasitaemic children at 18 months
| Antigen tested/parasite isolate | Median antibody levela (IQRb) Number of seropositivec children (%) |
p valued | ||
|---|---|---|---|---|
| All children; (n = 601) | Parasitaemic children; (n = 60) | Aparasitaemic children; (n = 541) | ||
| MSP1 19kDe | 2.80 (0.65, 7.09) | 12.31 (4.38, 28.79) | 2.37 (0.56, 6.08) | < 0.0001 |
| 327 (54.4) | 53 (88.3) | 274 (50.7) | < 0.0001 | |
| MSP2f | 2.91 (0.87, 9.04) | 15.14 (3.47, 35.16) | 2.62 (0.79, 7.28) | < 0.0001 |
| 162 (26.9) | 36 (60.0) | 126 (23.3) | < 0.0001 | |
| EBA175g | 3.38 (1.95, 16.09) | 5.89 (2.89, 21.37) | 3.24 (1.92, 15.89) | 0.0228 |
| 69 (11.5) | 15 (25.0) | 54 (9.9) | 0.001 | |
| Rh2A9h | 7.17 (2.1, 25.3) | 8.59 (3.28, 19.24) | 7.11 (4.05, 13.27) | 0.5630 |
| 151 (25.1) | 23 (38.3) | 128 (23.7) | 0.013 | |
| Schizont | 3.30 (1.27, 8.09) | 17.31 (5.22, 48.66) | 2.95 (1.09, 6.98) | < 0.0001 |
| 325 (54.1) | 58 (96.7) | 267 (49.4) | < 0.0001 | |
| E8Bi | 0 (0, 0.20) | 0.15 (0, 0.86) | 0 (0, 0.16) | < 0.0001 |
| 43 (7.2) | 9 (15.0) | 34 (6.3) | 0.013 | |
| R29i | 0 (0, 0.07) | 0 (0, 1.12) | 0 (0, 0.002) | < 0.0001 |
| 21 (3.5) | 9 (15.0) | 12 (2.2) | < 0.0001 | |
| 3D7i | 0 (0, 0.35) | 0.30 (0, 2.08) | 0 (0, 0.29) | < 0.0001 |
| 50 (8.3) | 17 (28.3) | 33 (6.1) | < 0.0001 | |
Significant p value in italic format
aAntibody levels expressed as units relative to positive control
bInterquartile range
cSamples defined as antibody positive if levels greater than mean + 3SD of negative controls
dp value between parasitaemic and aparasitaemic children calculated by Mann–Whitney test or Chi squared test for antibody level or seropositivity, respectively
eMerozoite surface protein 1
fMerozoite surface protein 2
gErythrocyte binding antigen 175
hReticulocyte binding protein homologue 2A
iVariant surface antigen antibody responses