MEDICINE AND HEALTH CARE

THE HISTORICAL ROLE OF MEDICINE AND HEALTH CARE

Many medical historians agree that practitioner-provided medical interventions played only a small, perhaps negligible, role in the historical decline in population mortality rates. Effective medicine is a fairly recent phenomenon, and the delivery of effective medical interventions on a scale sufficient to affect population health indicators most likely appeared only well into the twentieth century. Though the magnitudes of other causes of mortality declines are still disputed, it is clear that a larger role, one of the most significant ones, might be attributed to public health measures and the spread of knowledge of the sources of disease. However, a number of scholars in this field attribute the largest share of the credit to improvements in environment, particularly to the greatly increased supply of foodstuffs that became available due to the agricultural and industrial revolutions.

The Rising Population and the Role of Medicine
The notion that medicine played a relatively minor historical role is certainly not new, and it has been asserted by researchers of various ideologies. This point of view is associated with the work of Thomas McKeown (1976), who focused on the dramatic rise in population in England and Wales from 1750 to the modern day. The pattern of world population growth, including population growth in England and Wales, has interested many scholars, including McKeown. World population is hard to estimate for the distant past, but research by the United Nations (1996) and others show that something extraordinary happened during the last 300 years. In the first century the population was roughly 300 million. For a thousand years thereafter, until the era of Viking ships, little or no change occurred. By the Age of Enlightenment, starting just before 1700, the population may have risen to 600 million. Then things began to change rapidly. Within a single century, the world population passed 1 billion people. The next 5 billion arrived within a mere 200 years. What had happened? Figure 5-2, based on United Nations data, reveals this startling pattern.

Returning to the history of England and Wales, the large rise in their populations in the period following 1750 is to a large degree a story of the population’s health. Population increase comes from increased birth rates, reduced mortality, or increased net in-migration. Migration was not an important source of population increase in England and Wales; when accurate birth rate and death rate data became available from 1841, these data alone proved able to account for the population change. Likewise, fertility probably did not account for the change because recorded birth rates have declined during the period since data have become available. Declines in birth rates are a common finding in countries undergoing industrialization and modernization. In contrast, recorded mortality rates did decline substantially. McKeown began by investigating which diseases contributed to the decline in death rates. Mortality data are very limited prior to the mid-1800s, but the records revealed an emerging picture. Table 5-1 shows death rates by disease category for three time periods. The table shows that airborne infectious diseases account for the largest single portion of mortality reduction, and waterborne infectious diseases also make up a substantial portion of known causes. Regarding the airborne diseases, other data suggest that the main airborne diseases showing a decline in mortality include tuberculosis, bronchitis, pneumonia, and influenza.