CD4 and malaria: Flow cytometric analysis of non-CD4 T cells and monocytes demonstrated a significant increase in the percentage of cells in early apoptosis (Annexin V+) in P. vivax-infected donors (2.03% and 1.93%, respectively) compared to malaria-naive donors (0.99% and 0.14%, respectively) (p < 0.0001 for both, see Additional file 1).