TLR4 and infectious disease: Polymorphisms in TLR4 gene, which is located in chromosome 9q33.1, has been implicated so far in the pathogenesis of several infectious diseases, including bacterial23–25, fungal26, parasitic27, and some viral infection, such as human immunodeficiency virus28,29, Kaposi sarcoma-associated herpesvirus30, and respiratory syncytial virus (RSV)31.