Indoor exposures to House Dust Mite allergen (Der p 1) and fungi are associated with asthma. Identification of seasonal variation in these allergen levels would help in the management of patients with asthma. Aim: To examine the seasonal variation in indoor levels of Der p 1 and ergosterol in dust and airborne fungi. Methods: Floor dust was collected from the bedrooms of 40 houses at four times longitudinally over one year. Dust was analyzed for Der p 1 levels using a standardized enzyme linked immunosorbent assay and for Ergosterol, which is a marker of cumulative fungal biomass exposure by HPLC. An Andersen sampler was used in the bedroom to collect fungal propagules. Viable species were identified by standard methods. Variation in allergen levels over time was examined using repeated measures analysis of variance. Results: Season was significantly associated with levels of Der p 1, total fungi and ergosterol. Der p 1 levels were lowest in winter and highest in autumn with a trend for levels to increase across the other seasons. Total fungal levels were also lowest in winter with a trend of increasing levels across seasons until summer followed by a small decline in Autumn. Ergosterol levels were lowest in spring and higher in summer and autumn. Seasonal variation in total fungal levels was related to indoor temperature but levels of Der p 1 and ergosterol were associated with season independent of temperature, humidity and residential characteristics. Conclusions: Indoor levels of Der p 1, airborne fungi and ergosterol were higher in summer and autumn. Knowledge about the seasonal variation in allergen should be applied to minimise exposure.
|Number of pages||1|
|Issue number||SUPPL. 1|
|Publication status||Published - 1 Dec 1999|
- Der p 1