Fig. 2

IgG to PfGPI and risk of falciparum and vivax-malaria in Papua New Guinean children. Data are plotted as incidence rate ratios and 95% confidence intervals over 16 months of follow-up, adjusted for age, season, village of residency, haemoglobin levels and Gerbich blood type (n = 223). Black and white circles represent children with medium and high antibody levels, respectively. Clinical malaria was defined as axillary temperature ≥ 37.5 °C or history of fever in the preceding 48 h with a current P. falciparum parasitemia of > 2500 (n = 383); > 10,000 (n = 315); and > 50,000 parasites/μL (n = 175); and P. vivax > 500 (n = 301); > 2000 (n = 207); and > 10,000 parasites/μL (n = 90). IRR, 95% confidence intervals and P values are from negative binomial GEE models