ABSTRACT
Airborne fungi are considerate the main agents related to allergy in patients that suffer from asthma and rinitis. The knowledge about the prevalence of these microorganisms and theis seasonal variation can be useful for human health by improving the diagnosis and treatment of respiratory allergic disease provoked by their inhalation. The present study has isolated and identified airborne funfi from São Luis city investigating their prevalence, biodiversity and seasonal variation. Samples were taken by the Petri plate gravitacional method in six urban areas. A total of 2993 fungal colonies were counted, 67,9% in the dry season and 32,1% in the rainy season. Statistical analysis showed that there are significant diference (p=0,0121) between the averages of spores in dry and rainy periods. Relative humidity, rainfall precipitation and wind speed can have influenced the diversity and concentration of fungal spores presents in the air. Among 24 genera isolated, the most prevalent ones were Aspergillus (38,7)%, Fusarium (13,90%), Curvularia (11,18%) and Penicillium (10,88%), major triggers of allergic process worldwide recognized. The data show the presence of a large number of airborne fungi spores in São Luis and all genera found are opportunistic and they may cause disease in susceptible patients.