CD8A and scrub typhus: From human cases, we know that during the acute phase of scrub typhus (on admission to the hospital) there is elevation of several cytokines such as IFN-γ, IL-18, IL-12(p40), TNF-α, T cell-targeting chemokines (CXCL9 and CXCL10), and of granzymes A and B, which are indicators of NK cell or CD8+ T cell activation, or both (Iwasaki et al., 1997; Chierakul et al., 2004; de Fost et al., 2005).