Reduction in Aspergillus and Penicillium Spore Counts Results in Reduction of Aspergillus and Penicillium Antigen Level in House Dust

Abstract

RATIONALE: Spores of the genera Aspergillus and Penicillium are commonly found in the indoor environment. To investigate the impact of indoor spore reduction on indoor fungal antigen exposure we conducted the following studies. METHODS: Subject households were recruited from the Kansas City area. Parents of children seen in the Allergy/Asthma Clinic were able to participate. Households containing at least 3 persons and at least 1 child with a history of respiratory disease (asthma, rhinitis, etc) were enrolled. Homes were inspected for the presence of asthma triggers using a standard protocol before repair and again 6 months after repair efforts were complete. Home repair included dehumidification, carpet and drywall removal and HVAC service. Non-viable air samples were taken with an Allergenco MK-3. Aspergillus/Penicillium spores were not differentiated but identified as a group. Dust samples were taken for evaluation of fungal allergens by immunoassay. RESULTS: Of 200 homes recruited, 73 homes completed all sampling and follow up. 85% of the homes had airborne Aspergillus/Penicillium spore levels pre remediation and 61% had airborne Aspergillus/Penicillium post remediation. Mean airborne Aspergillus/Penicillium spore levels before remediation were 4109 spores/m3 of air and after, were 2272 spores/m3 of air. Detectable levels of Aspergillus/Penicillium antigenic material were found in the dust of all houses tested both before and after remediation. The sum of Aspergillus/Penicillium was decreased from a mean of 1.84 mcg/gram dust to 1.48 mcg/gram of dust after remediation (p>0.01). CONCLUSIONS: Reductions in indoor airborne Aspergillus/Penicillium spore levels were accompanied by reductions in Aspergillus/Penicillium antigenic material in house dust.