TLR9 and meningococcal meningitis: Specifically, the TLR9 1635A/G polymorphism (also referred to as 2848C/T in some studies) has been associated with thrombocytic thrombocytopenic purpura (TTP) [62], meningococcal meningitis [27], cytomegalovirus infection in fetuses and newborns [63], symptomatic malaria [26] and toxoplasmosis [64].