IGHE and Allergy: Since the prevalence of anti-Bla g 5 IgE ranges between 30–90% of the cockroach allergic population, it suggests that at least 7% of a given population might be at risk for a cross-reactive allergy to a GST vaccine, two of which (schistosome-GST and hookworm GST) are being suggested as potential parasite candidates in humans [39], [41].