Figure 2.

Seroprevalence and magnitude of immunoglobulin G and M (IgG and IgM) antibodies to Plasmodium vivax merozoite surface protein 3α (PvMSP3α) in children and adults with P. vivax malaria and uninfected adults. A, Seroprevalence of IgG and IgM antibodies against different regions of PvMSP3α. The positive threshold for seroprevalence was calculated as above the mean plus 3 standard deviations of absorbance detected in malaria-naive Australian donors. Numbers atop brackets are P values; the χ ² test was used for comparisons between groups. B, Cumulative IgG and IgM antibody responses targeting different regions of PvMSP3α. Data represent percentage of individuals who are positive for the protein regions tested. C, Magnitudes of IgG and IgM antibody responses against different regions of PvMSP3α. For boxplots, the lower and upper lines of boxplot represent the first and third quartiles, whisker lines correspond to the highest and lowest values no further than 1.5 interquartile range, and horizontal lines within boxes indicate medians. Data beyond the whisker lines are treated as outliers, represented as circles, squares and triangles. Numbers atop brackets are P values; the Mann-Whitney test was used for comparisons between groups. Abbreviation: OD₄₅₀, optical density at 450 nm.