Allergy to caddis fly (Trichoptera): I. The insect

Abstract

The physical and environmental features existing at the outlet of Lake Erie and at the head of the Niagara River create conditions under which caddis flies develop in great numbers. The immediate proximity to these waters of two cities—Buffalo and Fort Erie—exposes a large population to the emanations of these flies and results in the not uncommon occurrence of allergic sensitivity to them. A recent survey of the area disclosed the presence of twenty-three different species of caddis fly. Ninety-five per cent of the thousands of specimens collected, however, belonged to five species. The habits of the local species are described and observations are reported on water and meteorologic factors which influence the seasonal occurrence and the flight density of the adult flies and hence the intensity of human exposure to them. A brief note is made on the world-wide distribution of the caddis fly, and on other areas in the United States and Canada where concentrations of them exist. A second article is in preparation, covering the clinical aspects of allergy to the caddis fly.