Indeed, resistance to H. contortus is associated with potent polarized Th2 responses that are characterized by the presence of eosinophils, mast cells, and antibody production at the site of infection, as well as the production of type-2 cytokines such as IL-4, IL-5 and IL-13 in abomasal tissues or draining lymph nodes6–9. The gene discussed is IL5; the disease is infection.