Infection with the tapeworm Hymenolepis diminuta can abolish the epithelial ion transport abnormalities that accompany colitis. To reach these conclusions, C. Reardon et al. [(2001) Infect. Immun. 69, 4417–4423] utilized a mouse model of dextran sulfate sodium (DSS)-induced colitis – this leads to reduced ion responses to electrical nerve stimulation, acetyl choline receptor agonist carbachol or to the adenylyl cyclase activator forskolin. However, if the mice were infected with H. diminuta prophylactically or therapeutically, DSS-induced irregularities in ion-transport were significantly ameliorated. By contrast, H. diminuta infection did not alter the immune processes accompanying colitis, such as leukocyte infiltration, cytokine synthesis, edema and ulcerative damage. SHK