Fig. 3

IgG levels to 11 Plasmodium vivax proteins in relation to other variables. a The Thai volunteers were divided into P. vivax-negative (n = 299–524) and P. vivax-positive (n = 16–22) to determine associations of IgG levels with current infection. Statistical difference between the two groups was assessed using the Student’s t test. The 1/50 and 1/100 values of the immune control plasma pool are shown in black and blue lines, respectively. b The volunteers were divided into four age groups, 0–6 years (n = 56–89), 7–12 years (n = 58–107), 13–17 years (n = 32–48) and 18 years and older (n = 166–298), to determine associations of IgG levels with age. Statistical difference between age groups was assessed using a one-way ANOVA with Sidak’s multiple-comparisons test. c The volunteers were divided into two spatial groups (see Fig. 1): those living near the border, group 1 (n = 54–80), and those living near health facilities, group 2 (n = 261–466), to determine associations of IgG levels with spatial heterogeneity. Statistical difference between the two groups was assessed using the Student’s t test. In all panels, box-plots represent the median and interquartile range, error bars show the 5–95 percentile and filled circles show outlier values. ****p < 0.0001, ***p < 0.001, **p < 0.01, *p < 0.05