Fungal populations in the bedroom dust of children in Havana, Cuba, and its relationship with environmental conditions

Abstract

The study of the fungal community composition in house dust is useful to assess the cumulative exposure to fungi in indoor environments. The objective of this research was to characterize the fungal diversity of house dust and its association with the environmental conditions of bedrooms. For this, the dust was collected from 41 bedrooms of children between the ages of 8 and 9 with a family history of asthma, residents of Havana, Cuba. The fungal content of each sample was determined by two methods: plate culture with Malt Extract Agar and by direct microscopy. An ecological analysis was carried out from the fungal diversity detected. To describe the factors associated with the fungi detected, bivariate logistic regression was used. Through direct microscopy, between 10-2311 fragments of hyphae and spores corresponding mainly to Cladosporium, Coprinus, Curvularia, Aspergillus/Penicillium, Xylariaceae, and Periconia were identified. Through the culture, 0–208 CFU were quantified, where Aspergillus, Cladosporium, and Penicillium predominated. The culturability evidenced the differences between the quantification determined by both methods. A positive relationship was found between the type of cleaning of the furniture, the presence of trees in front of the bedroom, indoor relative humidity, indoor temperature, the presence of air conditioning by air conditioning and natural ventilation with specific spore types and genders. The use of two different identification methods allowed to detect a greater fungal diversity in the residences evaluated. Monitoring the exposure to these fungal allergens in childhood can help to prevent sensitization in the allergic child, the development of asthma and other respiratory diseases.

Indoor Built Environments Attended by Primary School Children and Its Microbiology: A Cross-Project Study

“…The results the research performed by [46] determined that the volume of the room, relative humidity, and floor levels play an important role in fungal concentrations. Similarly, in another research performed by [53], indoor RH and indoor temperature exerted a positive relationship with specific spore genera as well as other dwelling characteristics such as the type of cleaning of the furniture, the presence of trees in front of the bedroom, the presence of air conditioning, and natural ventilation. A previous study on dwellings revealed positive associations between electrical heating and fungi [54].…”