Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 13 4 2014 08 15 290 295 EN Nicolae Ovidiu Berghi Anima Medical Center, Bucharest, Romania. 2015 10 16 Opening frontiers has led in the last two decades to a massive migration of Romanians to Spain and Italy, two countries known to have large areas planted with olives. Romania owns large areas planted with ash forests. Because of cross-reactivity between these two trees belonging to the Oleaceae family and the big allergenic potential of olive pollens, after a number of years of residence in these countries, many Romanians will present allergic respiratory symptoms of rhinitis and asthma, both in the season of olive pollination and ash pollination. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/443 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/443/394