IL4 and infection: While the cellular response to enteric fever infection is Th1 dominated, Th2 cytokines may be modulated by infection, with S. Typhi-specific IL-13 secretion observed in peripheral blood mononuclear cells isolated during typhoid fever convalescence (52) and IL-4 secreted at the apical side of intestinal biopsy specimens infected in vitro with S. Typhi (53).