Hypersensitivity to pollen of Olea europaea in Israel.

The incidence of skin-tested sensitivity to olive pollen allergens among subjects with suspected atopic respiratory allergy was investigated in various populations of Israelis. This incidence was correlated with the olive cultivars, with the abundance of trees in the patient's neighborhoods, and with the history of exposure of the studied populations to olive pollen. Positive skin reactions to olive pollen, among atopic patients of the Jewish population, is rather high where olive trees are abundant (66%), and lower (29%) where trees are scarce (P < 0.003). Sensitization was significantly lower (P < 0.003) among a population of Israeli atopic Arabs (16%), though these Arabs have lived in an olive-rich area for several generations.