At the onset of the COVID-19 pandemic, Rajamanickam A (2021) analyzed a wide range of immunological parameters in LTBI subjects [25], finding significantly different plasma levels for IFN γ, IL-2, TNF α, IL-1 α, IL-1 β, IL-6, IL-12, IL-15, IL-17, IL-3, GM-CSF, IL-10, IL-25, IL-33, CCL3, and CXCL10 in LTI along with COVID-19. Here, IL15 is linked to COVID-19.