Notably, mice in Th1 polarised settings (including IL-4 deficient or IL-10/IL-4 double-deficient mice) exhibit rapid weight loss at the onset of egg production, elevated expression of proinflammatory Th1 cytokines and mediators, and high levels of mortality between wks 8-10 of infection (10, 32, 101). This evidence concerns the gene IL4 and infection.