FCGR2A and respiratory system disorder: Dengue virus has been associated with antibody-dependent enhancement of disease following the generation of humoral antiviral responses.71 Respiratory syncytial viruses and some feline coronaviruses have been associated with a phenomenon called vaccine-associated enhanced respiratory disease, which can develop after humoral immune responses.72 It is unclear whether the alteration of macrophage phenotypes in response to the binding of FcγR by viral ICs may contribute to the exacerbation of forms of respiratory disease.