The appearance of IL‐10‐expressing CD4+ T cells during Plasmodium infection in humans16, 17, 18, 30, 31 and mice32, 33 has been well documented, and early reports associated cerebral malaria in children with high circulating IL‐10 levels34, 35, 36: one study found IFN‐γ/IL‐10‐co‐producing cells in children with severe malaria.17 The gene discussed is CD4; the disease is malaria.