IGHE and infection: This requirement led to severe recruitment problems as (1) heavily infected and exposed individuals (i.e. at highest risk of infection) had total IgE levels that were considerably in excess of the upper IgE limit for inclusion (≤1300 IU/mL); and (2) allergic individuals (with a disease profile likely to respond to omalizumab therapy) have a low risk of infection with geohelminth parasites.