Fungi can cause disease of man in two ways: 1. They may produce an infection. 2. Contact of fungi with mucous membranes may result in absorption of antigenic material with consequent development of hypersensitiveness without infection; subsequent contact with the same fungi results in an allergic reaction. In the past few years increased attention has been directed toward this hypersensitiveness to fungi without infection, although the condition has been known since the work of Storm van Leeuwen.1 Many cases are now on record and the routine use of fungus extracts in allergic skin tests is becoming the accepted practice. Such routine tests indicate that, in certain geographical locations at least, an appreciable percentage of allergic patients is sensitive to fungi; the work of Durham2 indicates that the atmospheric concentration of fungus spores may approximate that of ragweed pollen grains.
In most of the cases reported the patients are