Infections from HSV-1, HSV-2, KSHV, and EBV have been shown to stimulate TLR9-mediated production of type I IFN in pDCs (Lund et al., 2003; Krug et al., 2004; Fiola et al., 2010; West et al., 2011; Ma and He, 2014). Here, TLR9 is linked to infection.