PTAFR and infection: During infection, blood coagulation is activated to limit the spread the of the pathogen; however, overactivation may occur resulting to thrombosis, excessive inflammation, and tissue damage.41 In this study, we observed in children with severe RSV had an overexpression of a tyrosine-protein kinase LYN gene, which is associated with blood coagulation and platelet signaling.42 Another upregulated gene we observed is the G-protein-coupled platelet-activating factor receptor (PTAFR) gene.