Allergic sensitization to airborne pollens in Brazil

Introduction: Pollen-induced respiratory diseases represent a growing health burden in Brazil, influenced by environmental exposures and climate change. Despite their clinical relevance, pollinosis and pollen sensitization remain underdiagnosed and poorly characterized across the country’s diverse ecosystems. Objective: To review the epidemiology, clinical relevance, and diagnostic challenges of allergic sensitization to airborne pollen in Brazil, with an emphasis on regional perspectives to support personalized treatment. Methods: The ASBAI Committee on Allergens conducted a narrative review of studies published through February 2026 using the PUBMED, LILACS, and SCIELO databases. Studies addressing aerobiology, pollen sensitization, the prevalence of pollinosis, molecular diagnosis, and allergen immunotherapy in Brazilian populations were evaluated. Thirty-eight studies met the inclusion criteria. Results: Reported sensitization rates ranged from 12 to 45%, depending on the geographic region and population studied. The most relevant allergenic source was Lolium multiflorum (L. multiflorum) pollen, particularly in southern Brazil, where well-defined pollen seasonality has been associated with respiratory symptoms and may be influenced by climate change and agricultural practices. Evidence from other regions remains limited, although sensitization to tropical grasses and cashew tree pollen has been documented. Advances in component-resolved diagnosis have improved the identification of genuine sensitization patterns and may help guide indications for allergen immunotherapy. However, the characterization of relevant Brazilian pollens and the standardization of allergen extracts remain insufficient. Conclusions: Allergic sensitization to airborne pollen in Brazil is heterogeneous and strongly influenced by regional flora and environmental conditions. Addressing current knowledge gaps requires establishing a national aerobiological monitoring network and modernizing allergen immunotherapy through molecular standardization, thereby aligning clinical practice with advances in precision medicine.