In this study, we demonstrated that distinct immune cells underwent different levels of apoptosis kinetically in vivo over the course of infection and confirmed the cell types (B cells, CD4 T cells, monocytes, and dendritic cells) that were mainly affected by ASFV infection and accounted for the leukopenia documented in many studies (Carrasco de Lara et al., 1996a; Oura et al., 1998; Karalyan et al., 2012; Walczak et al., 2021). Here, CD4 is linked to infection.