Table 4.
Prevalence of Plasmodium Falciparum Infection at the End of Season Surveys Overall Which Were Conducted Approximately 1 Month After the Last Administration of SMC, and Approximately 5 Months After the Last Dose of Priming or the Booster Vaccine was Given, by Study Year
| Anti-CSP Antibody Titer by Tercile | n/N | Prevalence (95% CI) | Prevalence Ratio (95% CI) | P Value |
|---|---|---|---|---|
| Overall | ||||
| Lowest | 22/237 | 9.28 (6.19–13.7) | [Ref] | - |
| Medium | 17/244 | 6.97 (4.37–10.9) | 0.71 (.40–1.24) | .223 |
| Highest | 13/224 | 5.80 (3.40–9.75) | 0.70 (.37–1.33) | .274 |
| 2017 | ||||
| Lowest (0.95–293.5 EU/mL) | 1/58 | 1.72 (.24–11.4) | [Ref] | |
| Medium (297.6–570.6 EU/mL) | 0/62 | 0 | 0 | - |
| Highest (601.0–2599.1 EU/mL) | 2/54 | 3.70 (.92–13.8) | 2.18 (.20–23.39) | .52 |
| 2018 | ||||
| Lowest (8.2–185.6 EU/mL) | 10/91 | 11.0 (6.00–19.3) | [Ref] | |
| Medium (188.0–381.4 EU/mL) | 11/90 | 12.2 (6.88–20.8) | 1.08 (.51–2.30) | .84 |
| Highest (382.5–1635.4 EU/mL) | 6/80 | 7.50 (3.40–15.8) | 0.81 (.33–2.00) | .65 |
| 2019 | ||||
| Lowest (5.3–137.3 EU/mL) | 11/88 | 12.5 (7.04–21.2) | [Ref] | |
| Medium (137.5–263.3 EU/mL) | 6/92 | 6.52 (2.95–13.8) | 0.43 (.17–1.05) | .063 |
| Highest (266.5–1074.5 EU/mL) | 5/90 | 5.56 (2.32–12.7) | 0.40 (.15–1.05) | .062 |
Poisson regression models for the pooled analysis over all 3 surveys were adjusted for study year and the age of the child. The overall analysis aggregates the number of children testing positive for Plasmodium falciparum and the total number of children for the tertiles defined separately in each year, and for children above and below the specific threshold in each year of the study.
Abbreviations: CI, confidence interval; EU, enzyme-linked immunosorbent assay unit.