2019 Yes https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6555650/ Baxi, Sachin North America Review Students Elementary (K-5) Fungi Absenteeism Respiratory symptoms Fungal spores were present in all classroom samples. The geometric mean of the total fungi was 316.9 spores/m3 and ranged from 15.0 to 59,345.7 spores/m3. There was variability in total fungus quantity between schools and classrooms within the same school. Mitospores were the most commonly detected fungal grouping. Investigation of the individual mitospores revealed that exposure to Alternaria was significantly associated with asthma symptom days in students sensitized to Alternaria (OR = 3.61, CI = 1.34-9.76, P = .01), but not in children not sensitized to Alternaria (OR = 1.04, CI = 0.72-1.49, P = .85). Students sensitized to Alternaria and exposed to high levels (≥75th percentile exposure) had 3.2 more symptom days per 2-week period as compared with students sensitized but exposed to lower levels.