2021 Yes https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12865 Adams, Rachel I Europe Observational Students Elementary (K-5) Bacteria Fungi Respiratory symptoms Bacteria Built environment Classrooms Fungi Indoors microbiome Cold Mycobiome In Finland, there were several positive associations between particular microbial indicators (diversity, richness, individual taxa) and a respiratory symptom score, while in the Netherlands, the associations tended to be mostly inverse and statistically non-significant. In Finland, abundance of the Sphingomonas bacterial genus and endotoxin levels partially explained the associations between moisture damage and symptom score. A few microbial taxa explained part of the associations with health, but overall, the observed associations between damage-associated individual taxa and respiratory health were limited.