High levels of Olea europaea pollen and relation with clinical findings

Background: Olea europaea pollen is an important cause of seasonal allergic rhinitis and bronchial asthma in southern Spain. For patients allergic to grass pollen the critical concentration of airborn pollen is 50 grains/m(3) , but in the case of Olea pollinosis no data is available. Methods: Fifty-s ix seasonal allergic rhinitis patients (29 in 1994 and 27 in 1995) were inc luded in this study, all of whom lived in Jaen. Daily symptom card were fil led in and pollen counts during May and June were performed in both years. A linear regression model was used for analysis of the airborne pollen conc entration and the symptom score. Results: Significant correlations among da ily counts of Olea pollen and rhinitis symptoms were obtained. Most of our monosensitized patients needed a high Olea pollen concentration in the atmo sphere (around 400 grains/m(3)) to suffer at least from mild allergic rhini tis symptoms. Conclusion: Local conditions with a wide a rea dedicated to o live tree cultivars result in a high concentration of this pollen in the at mosphere, Monosensitized Olea patients in our area seem to need exceptional ly high levels to suffer from allergic symptoms.