Allergenic fungal spores and hyphal fragments in the aerosol of Havana, Cuba

摘要

Fungal spores have a recognized allergenicity, but in recent years, fungal fragments have also been reported as inducers of Type I allergy. However, airborne hyphae are scarcely studied in tropical regions. The objective of this research was to analyze the fungal composition of the Havana aerosol during 2017 and 2018, emphasizing the presence of hyphae fragments. Air sampling was performed using a Lanzoni VPPS-2000 sampler. The fungal propagules collected were identified and counted following the recommendations of the Spanish Aerobiology Network in two longitudinal transepts of each daily slides. In 2017, the spore count and hyphae count were higher than in 2018 (108,607 spores and 3822 fungal fragments vs. 40,896 spores and 2268 fungal fragments). Cladosporium was the most abundant spore (77.2-76.6%), predominating in the month of May. Leptosphaeria ascospores were identified at lower levels (16.2-17.9%) but also abundant during May. The behavior of the hyphal fragments does not show great variations throughout the year. The contribution of this component to the aerosol ranged between 3.4 and 5.3% in 2017 and 2018, respectively. The intradiurnal periodicity showed a diurnal pattern for Cladosporium and nocturnal for Leptosphaeria, while the hyphae pattern does not show great variations. The temperature and relative humidity correlated with the concentration of the detected airborne fungi propagules. The composition of the fungal aerosol in Havana during the 2 years was characterized, including both spores and hyphal fragments, since both structures can be related to respiratory allergy pathologies.