Seasonal Variation of Mortality in Queensland

Queensland mortality shows a seasonal, age‐dependent variation in cardio‐vascular and respiratory diseases, although not in malignant neoplasms. The hypotheses previously put forward to explain the winter increases in respiratory disease and cardiovascular disease are discussed and a new hypothesis is considered, that the winter rise in cardiovascular disease is due to decreased exposure to ultraviolet radiation. It is concluded that the relative importance of the factors which may be causing the seasonal variations in disease, will have to be determined by analytical studies of individuals.