Schistosomiasis is a systemic infection that is known to induce an early IFNγ response that transitions to a mixed response where IL-4 and IL-13 production is greater than IFNγ by 10-weeks post infection [16, 17], and IL-4Rα driven alternative activation of macrophages is essential for host survival, as mice that lack signaling die of acute disease [18–20]. Here, IL4 is linked to infection.