IFNG and viral infectious disease: Viral infection with COVID-19 could present as lymphocytic vasculitis similar to the thrombophilic arteritis induced by immune complex–activated cytokines.7,13 The herpes virus is also known to activate interleukin-1, IFN-gamma, and tumor necrosis factor-alpha, leading to the recruitment of cytotoxic and natural killer cells that target the keratinocytes.13 The immune response to infection also leads to Langerhans cells activation, resulting in a state of vasodilation and spongiosis.7,13