ABSTRACT
Although case reports of allergic reactions go back to the Pharaohs, the rise of allergic disease to become one of the common diseases of mankind has occurred over the 1850s. Three main phases of the increase can be recognized: hay fever, asthma, and peanut allergy. Without some form of exposure, sensitization to common inhalant allergens does not occur. Thus, very few children raised in Los Alamos, New Mexico or the Norbotten region of Sweden are sensitized to mite or cockroach because these allergens are neither present in their homes nor in the homes of their neighbors. The first indication that the skin might be a route for sensitization came in 1931 when Taliafero demonstrated that patients with schistosomiasis had serum reagins to schistosomules. The implications were clear: schistosomules going through the skin could induce sensitization and this sensitization might play a role in protection against further infestation.
