Allergic asthma is responsible for widespread morbidity and mortality and its incidence has increased dramatically in industrialized countries over the past two decades. Here, we describe a new murine model of allergic asthma utilizing a novel allergen with intrinsic enzymatic activity similar to that reported for many environmental allergens. The allergen, NES, is excreted and secreted from the nematode Nippostrongylus brasiliensis, and can readily be isolated from in vitro parasite cultures. When NES is administered intranasally to presensitized mice, allergic airway disease develops, including airway hyper-responsiveness, airway eosinophilia, IgE antibody production and Th2 cytokine production. This disease is characteristic of atopic asthma and can be induced within 11 days, thus providing a platform for the rapid analysis of allergic disease and high throughput testing of immunomodulatory factors.