Helminthic infections and allergic disorders including asthma, rhinitis and eczema are major public health problems. While helminthic infections are prevalent mainly in developing countries, allergic disorders are more common in developed industrialized ones. This has lead to the assumption that helminth infections protect against allergy. Studies in experimental animals have shown that infections with some helminths or immunization with helminth derived products suppress the development of allergic diseases. The suppressive effect of helminths has been attributed to the induction of...