Table 3.
Number (%) of participants seroprevalent for stage-specific malaria antigens by malaria-resistant status and time, the Mother–Offspring Malaria Study, 2002–2006
| Antigens | Week 24 | Week 48 | Week 76 | Week ≥ 100 | P trend for time† | Total occurrences |
|---|---|---|---|---|---|---|
| Sporozoite and liver stage | ||||||
| CSP | ||||||
| Nonresistant | 98 (29.3) | 93 (32.4) | 96 (37.7) | 131 (41.2) | 0.009 | 418 (35.0) |
| Malaria resistant | 15 (41.7) | 9 (27.3) | 11 (52.4) | 9 (42.9) | 0.121 | 44 (39.6) |
| SLARP | ||||||
| Nonresistant | 58 (17.4) | 80 (27.9) | 100 (39.2) | 140 (44.0) | <.0001 | 378 (31.7) |
| Malaria resistant | 6 (16.7) | 15 (45.5) | 8 (38.1) | 10 (47.6) | 0.821 | 39 (35.1) |
| Late liver stage | ||||||
| LISP1* | ||||||
| Nonresistant | 58 (17.4) | 49 (17.1) | 67 (26.3) | 126 (39.6) | < 0.0001 | 300 (25.1) |
| Malaria resistant | 2 (5.6) | 5 (15.2) | 1 (4.8) | 7 (33.3) | 0.210 | 15 (13.5) |
| Merozoite stage | ||||||
| MSP1* | ||||||
| Nonresistant | 84 (25.2) | 94 (32.8) | 92 (36.1) | 91 (28.6) | 0.482 | 361 (30.2) |
| Malaria resistant | 2 (5.6) | 1 (3.0) | 3 (14.3) | 0 (0.0) | 0.744 | 6 (5.4) |
| AMA1* | ||||||
| Nonresistant | 120 (35.9) | 73 (25.4) | 88 (34.5) | 116 (36.5) | 0.0002 | 397 (33.3) |
| Malaria resistant | 6 (16.7) | 0 (0.0) | 2 (9.5) | 0 (0.0) | 0.017 | 8 (7.2) |
AMA1 = apical membrane antigen 1; CSP = circumsporozoite protein; LISP1 = liver specific protein 1; MSP1 = merozoite surface protein 1; SLARP = sporozoite and liver stage asparagine-rich protein. Seroprevalent cut-point defined as mean + 2 × standard deviation of log-transformed level from a nonimmune U.S. adult (N = 20).
P < 0.05, differences between malaria-resistant and nonresistant children tested in unadjusted generalized estimating equation (GEE) models (binomial distribution, autoregressive correlation matrix).
P test for trend: Week entered as ordinal variable (week 48 − week ≥ 100), modeled in GEE models (Autoregressive correlation matrix).