Levels of IgE and IgG4 against schistosome adult worm and egg antigens as well as those against the house dust mite Dermatophagoides pteronyssinus (Derp1) allergen – one of the most important allergen in clinical allergy (20) and prevalent in Zimbabwe (21) – were quantified before a single dose of PZQ was given and 6 weeks later. Here, IGHE is linked to allergic disease.