IL17A and Flavivirus Infections: The mechanisms of γδ T cells function in flavivirus infections. After flavivirus infection, γδ T cells can be activated through various recognition mechanisms of the γδ TCR and TLR signaling pathways. Subsequently, they secrete cytokines (IFN-γ, IL-17A, or TNF-α), enhancing the systemic immune response. However, we must be cautious, as the prolonged presence of certain cytokines may exacerbate tissue damage. Additionally, they can directly kill virus-infected cells.