Figure 1.
IgG positivity to different PvMSP3α and PvMSP9 proteins.
(a) Cumulative IgG positivity for different PvMSP3α proteins. Data are plotted as the percentage of 183 individuals who are antibody positive for 0–4 of the proteins tested. (b) Associations between age and IgG positivity to PvMSP3α and PvMSP9 proteins. Children were divided into two age groups (<21 mths: n = 96, ≥21 mths: n = 87) to examine associations with age. P values≤0.05 were considered significant and are shown. (c) Associations between P. vivax infection status (post-PCR LDR-FMA positive: n = 90, negative: n = 93) and IgG positivity to PvMSP3α and PvMSP9 proteins. As indicated, the presence of P. vivax was determined by a semi-quantitative post-PCR ligase detection reaction-fluorescent microsphere assay (LDR-FMA). P values≤0.05 were considered significant and are shown.
Table 1.
Optical density values (OD) as a measurement of total IgG to different PvMSP3α and PvMSP9 proteins.
Table 2.
Association between antibody positivity and protection against subsequent P. vivax malaria (density>500/µl).
Figure 2.
Association between antibodies to PvMSP3α(Block II) and PvMSP9(N-terminal) proteins and risk of P. vivax malaria.
Data are plotted as exposure and age adjusted incidence rate ratios (aIRR(exp)) ± 95% confidence intervals for febrile episodes with different levels of concurrent P. vivax parasitaemia.