Aiyedun et al. 21 also noted an absence of a delayed skin test response in guinea worm patients, and Knoop et al. 24 subsequently showed a diminished ThI‐type 1 cytokine response in subjects with an active infection together with enhanced IL‐10 production on stimulation with guinea worm and cross‐reactive antigens in keeping with these earlier findings. The gene discussed is IL10; the disease is infection.