IGHG3 and malaria: Total IgG, IgG1 and IgG3 against PfRh4.2 were all significantly associated with protection from clinical malaria (defined as parasitemia >5000 parasites/μl plus fever) when comparing high and low antibody responders (HR 0.23, p<0.0001; 0.36, p = 0.001 and 0.4, p = 0.003, respectively, Table 3).