Immunochemical and Physical Quantitation of Grass and Olive Pollen Allergens: Correlation With Asthma Admissions in Cáceres, Spain.

Background and Objectives: The association between pollen counts and allergen levels in the air is controversial. Objectives: The aims of the study were to quantify total and major allergen levels of Phleum pratense and Olea europaea and to analyze their correlation with grass and olive pollen counts and the number of asthma attacks attended at Complejo Hospitalario Universitario, Cáceres, Spain.
Material and Methods: A volumetric air sampler and a Burkard spore trap were used for pollen and aeroallergen collection during April- June 2011. Filters were extracted, and major allergens were quantified using enzyme-linked immunosorbent assay.
Results: May was the main grass pollination period, with a maximum peak of 1362 grains/m3 (May 13). The main pollination period for olive was April 30-May 20, with a maximum peak of 851 grains/m3 (May 11). A moderate correlation was observed between asthma exacerbations and grass pollen counts or Phleum total allergen levels; this became stronger when a 3-day offset was introduced. A significant association was observed between asthma exacerbations and total olive allergen or olive pollen grain levels when a 1-day offset was introduced. The maximum correlation (moderate-high) was observed 4 days and 6 days away from the maximum olive pollen peak and the maximum Ole e 1 peak level, respectively.
Conclusions: This study reveals a significant correlation between grass and olive pollination and an increase in the number of visits to the emergency room for asthma attacks. The aerobiological pattern of allergen levels in the air is similar to that of pollen counts during the grass and olive pollination periods.