TABLE 3.
Prevalences, 95% confidence intervals, and normalized mean fluorescence intensities of IgG responses to five PvTRAgs, MSP1-19, and AMA1 in serum samples from human patients and healthy individuals
| Antigen | Sample | No. positive | No. negative | Sensitivity [total (%)] | Specificity [total (%)] | 95% CIa | Normalized MFIb (cutoff value) | P valuec |
|---|---|---|---|---|---|---|---|---|
| MSP1-19 | Patients | 90 | 10 | 100 (90.0) | 82.6–94.5 | 3.078 (6,679) | <0.0001 | |
| 5 yr | 6 | 24 | 30 (20.0) | 9.5–37.3 | 0.781 (6,679) | 0.002 | ||
| 12 yr | 2 | 28 | 30 (6.6) | 1.9–21.3 | 0.481 (6,679) | 0.910 | ||
| Healthy | 3 | 29 | 32 (96.8) | 75.8–96.8 | 0.456 (6,679) | |||
| AMA1 | Patients | 52 | 48 | 100 (52.0) | 42.3–61.5 | 1.259 (3,921) | <0.0001 | |
| 5 yr | 5 | 25 | 30 (16.7) | 7.3–33.6 | 0.799 (3,921) | 0.261 | ||
| 12 yr | 1 | 29 | 30 (3.9) | 5.6–12.7 | 0.558 (3,921) | 0.231 | ||
| Healthy | 2 | 30 | 32 (93.8) | 79.9–98.3 | 0.585 (3,921) | |||
| TRAg_16 | Patients | 75 | 25 | 100 (75.0) | 65.7–82.5 | 1.554 (4,796) | <0.0001 | |
| 5 yr | 4 | 26 | 30 (13.3) | 5.3–29.7 | 0.749 (4,796) | 0.257 | ||
| 12 yr | 0 | 30 | 30 (0) | 0–11.35 | 0.597 (4,796) | 0.588 | ||
| Healthy | 1 | 31 | 32 (96.9) | 84.3–99.5 | 0.622 (4,796) | |||
| TRAg_29 | Patients | 61 | 39 | 100 (61.0) | 51.2–70.0 | 1.384 (5,389) | <0.0001 | |
| 5 yr | 5 | 25 | 30 (16.7) | 7.3–33.6 | 0.734 (5,389) | 0.006 | ||
| 12 yr | 4 | 26 | 30 (13.3) | 5.3–29.7 | 0.640 (5,389) | 0.110 | ||
| Healthy | 1 | 31 | 32 (96.9) | 84.3–99.5 | 0.535 (5,389) | |||
| TRAg_26 | Patients | 54 | 46 | 100 (54.0) | 44.3–63.4 | 1.197 (3,079) | <0.0001 | |
| 5 yr | 3 | 27 | 30 (10.0) | 3.5–25.6 | 0.726 (3,079) | 0.662 | ||
| 12 yr | 0 | 30 | 30 (0) | 0.584 (3,079) | 0.731 | |||
| Healthy | 1 | 31 | 32 (96.9) | 84.3–99.5 | 0.618 (3,079) | |||
| TRAg_13 | Patients | 51 | 49 | 100 (51.0) | 41.4–60.6 | 1.157 (3,351) | <0.0001 | |
| 5 yr | 3 | 27 | 30 (10.0) | 3.5–25.6 | 0.767 (3,351) | 0.035 | ||
| 12 yr | 2 | 28 | 30 (6.6) | 1.9–21.3 | 0.639 (3,351) | 0.564 | ||
| Healthy | 1 | 31 | 32 (96.9) | 84.3–99.5 | 0.602 (3,351) | |||
| TRAg_15 | Patients | 60 | 40 | 100 (60.0) | 50.2–69.1 | 1.183 (3,238) | <0.0001 | |
| 5 yr | 18 | 12 | 30 (60.0) | 42.3–75.4 | 1.085 (3,238) | <0.0001 | ||
| 12 yr | 6 | 24 | 30 (20.0) | 9.5–37.3 | 0.714 (3,238) | 0.002 | ||
| Healthy | 1 | 31 | 32 (96.9) | 84.3–99.5 | 0.565 (3,238) | |||
a
CI, confidence interval.
b
Normalized MFI, fluorescence intensities divided by each cutoff value (2 standard deviations above the mean fluorescence intensity of the malaria-naive samples).
c
Differences in the total IgG level for each antigen between vivax malaria patients and healthy individuals were calculated with the Mann-Whitney U test. A P value of <0.05 was considered statistically significant.