Environmental exposures
| Reported Exposure | Number (%) Exposed | 95% Confidence Interval |
| Hot tub | 8 (2.7) | 1.3, 5.4 |
| Damp/Mildew | 25 (8.6) | 5.8, 1.2 |
| Down | 107 (37.0) | 31.7, 42.7 |
| Birds | 24 (8.3) | 5.6, 12.1 |
| Musty | 11 (3.8) | 2.0, 6.7 |
| Standing water | 26 (8.9) | 6.1, 12.8 |
| Potting soils and compost | 39 (13.3) | 9.9, 17.7 |
| Farm | 23 (7.9) | 5.3, 11.6 |