The reduced prevalence of allergic disorders in patients infected with helminths and in experimental animal models has prompted the concept of helminth therapy (HT). It was the successful outcome of cooperation between parasitologists, immunologists and epidemiologists, based on the host-parasite immune regulatory interactions. This new approach aims at helping allergic patients especially those with unmet medical needs such as treating severe steroid-resistant asthmatic patients. Although HT is successful in regulating the proinflammatory responses in the host, it may predispose to possible risk of side effects of live worm infections. Thus, it would be more practical to isolate and characterize specific helminth-derived products. Epidemiological and experimental studies of HT in allergic diseases were very promising. However, there are some considerations that should be taken in account for further clinical trials. This chapter highlights the interaction between helminth infection and allergic diseases, the current status of HT, its challenges and future perspectives.
Keywords: Airway hypersensitivity, Allergic disorders, Clinical trials, Helminth therapy, Helminth-derived products, IL-10, Immune regulation, Necator americanus larvae, Self-treatment, Treg cells, Trichuris suis ova.