Table 1 Association between IgM and IgG to the merozoite surface and risk of clinical malaria.

The cohort (n = 199) was stratified into three equal groups according to low, medium, or high levels (defined by tertiles) of IgM to the merozoite surface. Unadjusted hazard ratios (uHRs) and HRs adjusted for the predetermined confounders of age and location of residence [adjusted HRs (aHRs)] are presented. IgM levels were compared between low-versus-medium (LvM) and low-versus-high (LvH) groups for the risk of symptomatic malaria (fever plus >5000 parasites/μl). Calculations were based on the first episode only.

uHR [95% CI]PaHR [95% CI]
age/location
P
IgMLvM0.44
[0.23–0.81]
0.0090.62
[0.32–1.18]
0.15
LvH0.38
[0.20–0.81]
0.0020.47
[0.25–0.89]
0.02
IgGLvM0.51
[0.29–0.91]
0.0210.58
[0.32–1.06]
0.08
LvH0.24
[0.12–0.49]
<0.0010.3
[0.14–0.64]
0.002