A National Atlas of Disease Mortality in the United Kingdom

MOST people are aware of the fact that there are large geographical variations in the incidence of disease. Diseases such as malaria usually remain localized; others such as cholera and influenza tend to spread widely from their point of origin. Others again, such as typhus, reflect both characteristics, for, in ordinary circum? stances, they tend to be extremely localized spatially to regions or population groups, but, in abnormal circumstances (such as may accompany sudden mass movement of people in time of war) their usual features are entirely altered. It would appear that, in these cases, although the aetiological and predisposing factors are now fairly well known, the provocative factors or stimuli of the environment, while different in each case, occur only in specific geographical areas. This suggests that there is a much greater chance of dying of, say, malaria, cholera or tuberculosis if one's life is spent in one district rather than in another. Skin and lip cancer is twenty times more common among white inhabitants of the southern half of the U.S.A. than among those in the northern part; in the Soviet Union it is five to six times more common in the south than in the north. In Iceland and Japan 50 per cent of all male cancers are stomach cancers; in the U.S.A. the comparable figure is only 10 per cent, and in Indonesia it is still lower. Disease is a reaction for the worse, a maladjustment or maladaptation of the individual to adverse stimuli in the environment, the response being conditioned by the genetic make-up of the victim. Yet does not the environment itself influence heredity ? Recent research forces one to the conclusion (which is, however, often hotly disputed) that environment and heredity are not such irreconcilably opposite poles but one and the same thing. In this context, it should be appreciated that to the geographer the 'environment' is the whole gamut of influences, physical (inorganic), biological (organic) and sociocultural, that bear upon Man's welfare and which sometimes impair his health and promote disease. Physically, such factors as climate, solar or atomic radiations, the nature of the soil or water supply are important. For instance, the countries bordering on the south and the east of the Sahara experience cerebrospinal meningitis in a way in which no other part of the world compares. Epidemics occur only during the dry season when the Harmattan is blowing in the Sudan, Nigeria, Ghana and the inter? vening ex-French territories. All epidemics end at the same time?the end of April with the coming of the rains. Again, in therapy, we are all familiar with 'bracing* or 'tonic' climates, such as are experienced on our north-east coast, and the 'relaxing' or 'sedative' climates, such as occur along the south coast of Cornwall and the Exeter region. Exposure to ionizing radiations increases the risk of developing leukaemia; soft water is associated with higher death rates from cardiovascular disease; absence of iodine in the environment leads to goitre, and so forth.