Susceptibility to streptococcal infections may also be a genetic risk factor: mechanistically, Haapasalo et al [60] suggest interactions between bacteria and Complement Factor H (CFH) affect pathogeneticity, and found that a variant in CFH (rs1061170, CFH*Y402H) was weakly associated with severe streptococcal disease in European patients (speculatively, we would also highlight that mutations in CFH5 are associated with C3 glomerulonephritis in Cypriots [61], though the mechanism in that condition is unknown). Here, CFH is linked to C3 glomerulonephritis.