The Relation of the Seasonal Variation of Asthma to the Weather: An Australia-Wide Survey

Abstract

SYNOPSIS The monthly variation in the incidence of asthma is closely related to temperature. This study, based on the analysis of admissions to children's hospitals throughout Australia, confirms, for a wide range of climates, observations previously reported from Brisbane. The relation is twofold. In the months which normally have a mean temperature below 70°F (21.1°C), asthma increases with increase in temperature. When the temperature exceeds 70°, asthma decreases with increase in temperature, and this is further supported by observations in North Queensland. The incidence of asthma is also related to rainfall. In Perth, where most rain falls in winter, the major incidence of asthma follows in spring. In Brisbane, where most rain falls in summer, the major incidence of asthma follows in autumn. It is suggested that the geographical variation in the incidence of asthma may also be related to temperature and rainfall.

Biometeorological triggers in childhood asthma

“…Rainfall may also create an aerosol rich in allergens, thus increasing their penetration into the bronchi [29]. Coloured basidiospores have previously been implicated in autumn asthma and hay fever [17,25,30]. Their strong correlation in this study suggests that their release into the atmosphere in late summer may contribute to the autumn influx of asthmatics [9], but a spurious correlation may conceivably have arisen through similarity of seasonal patterns.…”

“…Previous attempts to define the association between environmental changes and asthma admissions have relied on descriptive [8]. simple statistical techniques [25] or multivariate analysis [ 14. 18].…”

Seasonal waves of asthma: A possible botanical cause

“…The seasonal patterns of grass-growth, airborne pollens, air spora, and house-dust mites were studied intensively in the Brisbane area (Derrick, 1967;Domrow, 1970;Mosa 1965~ 1967~, 1967bRees, 1964); the patterns, usually unimodal, were not convincing. Climatic sequences showed a complex relationship to the seasonal patterns seen in asthma admissions (Derrick, 1965(Derrick, , 1966(Derrick, , 1968(Derrick, , 1972Derrick and Szymanski, 1967). It was shown that maximal asthma attendances occurred in Brisbane when the mean ambient temperature was about 21oc and the dew point about 13.5oc.…”