CD4 and malaria: Our hypothesis that prolonged malaria exposure (or untreated chronic infections) as a risk factor for eBL is consistent with our finding that the frequency of exhausted CD4+ T cells to PfSEA1-1A were similar between eBL children and Kenyan adults, and were significantly higher compared to healthy Nandi children (p < 0.0001 and p = 0.0004, respectively, Figure S6A).