Polymorphisms in TLR2 and/or TLR4 genes and protein concentrations of TLR2 and TLR4 have been analyzed in several infectious and/or inflammatory diseases, such as tuberculosis [19], severe invasive infections by Streptococcus pneumoniae and Neisseria menigitidis [18,21], sepsis [20], infection by Legionella pneumophila [11], leprosy [11], infective endocarditis [32], Lyme disease [33], urinary tract infections [34], cytomegalovirus infection [23], respiratory syncytial virus infection [11], HIV infection [22], and malaria [11]. Here, TLR4 is linked to respiratory syncytial virus infectious disease.