Author: Anthony J. McMichael, ANU
Over the next half a century and beyond, two major, contrasting shifts in population health will affect the social and economic burdens of disease and the causes of premature death in the Asian region.
Pervasive and disruptive population-health developments could also affect the movement of people, social stability and geopolitical security. These projected shifts will have major implications for Australia.
The first health-related shift is the continuing rise in non-communicable diseases (NCDs) experienced in middle to later adulthood, owing to rises in wealth, middle-income consumerism, dietary changes and urbanisation. The World Health Organization now views this as a global epidemic (and a drag on social development), with 63 per cent of global deaths in 2008 attributable to NCDs, including cardiovascular diseases, cancers, diabetes and chronic lung diseases. These four diseases are growing disproportionately in low-income countries, a trend that is well underway throughout Asia. As infectious diseases recede and life expectancies rise, the burden of NCDs is increasing — along with related national economic burdens.
The second health-related shift will come from a continued deterioration of and changes to environmental and climatic conditions — changes that affect the foundations of population health. With the population of most Asian countries still growing, pressure on natural resources is escalating. Asia is also exposed to ongoing global environmental changes, particularly climate change. This category of risk is largely borne of ongoing threats to food yields, freshwater supplies, the instability of infectious-disease agents, and the diverse health consequences (physical and mental) of extreme weather events. Knock-on health impacts also occur in internally displaced groups and in those seeking refuge in neighbouring countries — and this can pose a health risk to receiving populations.
The combination of demographic, environmental and climatic stresses is likely to increase food insecurity in much of Asia. China, India, South Korea and others are now acquiring land in foreign countries outside Asia as insurance against domestic land and food shortages. And along with changes in food production and procurement methods, these stresses are likely to mobilise still more ‘emerging infectious diseases’ in the Asian region and further afield. Several have recently materialised in Asia and others have made their transit through the region to Australia. Recent examples include the outbreak of SARS and the H5N1 bird flu. New viral diseases from bats, displaced from their natural habitat and with wide regional fly-paths, have also infected humans in Malaysia, Bangladesh and Australia over the past 15 years.
These shifts will have significant implications for Australia. Biomedical, educational and training programs will be needed for the prevention and management of NCDs. Asian countries are not currently well prepared to handle this burden, and there is an opportunity to make and sell appropriate health-care technology to help with its management. Emergent risks from infectious disease may also place new demands on Australia’s health-care institutions, professional training and wider social policies. Regionally, there is a need for stronger and more-coordinated surveillance of infectious-disease risks and patterns. This surveillance should include inter-country trade in livestock, given it is a potential source of infectious disease and carries the potential to spread to humans.
As the impacts of environmental and climatic changes increase, and as competition for river water, groundwater and arable land escalates, there will be adverse social and political consequences. This will demand greater regional research collaboration to better understand the sources, dynamics, control and management of these changes. Australia has a moral responsibility to contribute to this research, and the situation poses an opportunity for postgraduate training and bilateral scientific-exchange programs. Australia must also plan effectively for situations of social and political tension that will likely foment conflict and displacement. The health ramifications for those involved will be diverse, and Australia must choose and balance its political, economic, moral and self-protective responses.
Both of the emerging types of risk to population health will place increased stress on public health systems. Remedial strategies, including a reliance on doctors and hospitals, will not suffice — these are not exclusively health-sector issues. Rather, Asia and Australia face a number of population-level health consequences resulting from major shifts in the region’s environmental and social conditions. Many of the health consequences are foreseeable and (partly) preventable — depending on what pre-emptive multi-sectoral action is taken. With the prospect of increased population movement, regional food stresses, and the ever-present (and probably increasing) risk of novel epidemics, better coordinated public health strategies are needed in the region. These strategies should include monitoring, information sharing, collaborative research and coordinated disaster response.
Meanwhile, changes in the level and profile of population health will be the ultimate markers of how well Australia and its Asian neighbours are collectively managing the journey into their shared future.
Anthony J. McMichael is Professor of Population Health at the National Centre for Epidemiology and Population Health, Australian National University.