CD38 and malaria: In a previous study, we found that control of the parasite following the infection of malaria‐naïve volunteers with P. falciparum‐infected RBC was associated with an increased frequency of CD4+ T cells co‐expressing CD38, but these did not have increased expression of CD4, were poor producers of IFN‐γ8 and appeared to be analogous to mouse CD4 T cells activated in vitro65 and markedly different from those we describe herein during clinical disease.