Given that mRNA vaccination induces polyfunctional (15) and durable (16) T cell responses more homogenously than infection, and a previous report indicating that CD4+ T cells coexpressing interferon (IFN)-γ and interleukin (IL)-10 can arise in the context of hybrid immunity but not after vaccination alone (17), it seems plausible that mRNA vaccination could alter the landscape of established T cell immunity. This evidence concerns the gene IFNG and infection.