Classroom Fungal Spore Exposure and Asthma Morbidity in Inner-City School Children

Sachin N. Baxi, Carter R. Petty, Chunxia Fu, William J. Sheehan, Perdita Permaul, Lianne Kopel, Watcharoot Kanchongkittiphon, Jonathan M. Gaffin, and others

Abstract: 

Rationale

The association between asthma morbidity and indoor fungal exposure in classrooms of asthmatic children is not well understood.

Methods

Children with asthma enrolled in the School Inner-City Asthma Study were tested for allergic sensitization to fungus at baseline and had asthma morbidity assessments by questionnaire quarterly throughout the school year. Concurrent fungus counts were obtained twice during the school year from the subjects classrooms and analyzed by direct microscopy. We performed a stratified analysis to determine the effect of fungus exposure on asthma morbidity, measured as maximum number of symptom days over the previous 2 week period.

Results

Classroom fungus levels and skin testing data were available for analysis in 189 students from 29 schools. Of these students, 14% (N=27) were sensitized to fungus. We found a significant dose response relationship between Penicillium/Aspergillus (Pen/Asp) levels and asthma symptom days. Those sensitized to fungus and exposed to higher levels of classroom Pen/Asp had significantly more symptoms (Rate ratio 1.64, 95% CI 1.01-2.65), p=0.04. Amongst the sensitized population, children in classrooms at the 90th percentile of Pen/Asp (121 spores/m3) had 5.1 asthma symptom days in a 2 week period compared to children at the 10th percentile (5 spores/m3) who had 3.0 symptom days. This effect was not seen in non-sensitized students (Rate ratio=0.99, 95% CI=0.82-1.18), p=0.88. There was no interaction demonstrated between season of fungus exposure and health outcomes.

Conclusions

In fungus sensitized asthmatic children, exposure to fungal spores in the classroom increases asthma symptom days. School/classroom interventions targeted at decreasing fungus should be considered.

Journal of Allergy and Clinical Immunology, Vol. 131, Issue 2, AB54

http://dx.doi.org/10.1016/j.jaci.2012.12.875

abstract No: 

196
    • AAAAI 2013 (69th)