A volumetric-aerobiologic study of seasonal fungus prevalence inside and outside dwellings of asthmatic patients living in northeast Netherlands.

Air sampling with an Andersen sampler was carried out over a period of 21 mo, in 28 houses of asthmatic patients with an allergy for moulds. Inside, the livingroom, bedroom, and kitchen were studied, and an additional outside sample was always taken. Indoors, Penicillium showed the highest concentration, especially in the autumn and winter months, while Aspergillus and yeasts were also found frequently. The outside air was dominated by Cladosporium and Alternaria during summer months and Botrytis, Aspergillus, Mycelia sterilia and Basidiomycetes all year round. The patients showed high sensitisation towards Aspergillus, irrespective of the concentrations of the airborne fungi.