On a dusty construction site in western China, Mr Tan is just another anonymous migrant labourer. But, the unassuming former farmer is also the face of a complex web of crises threatening global health.
On one level, 24-year-old Mr Tan is a symbol of China’s economic success, and similar growth patterns over recent decades in other developing economies. Half a million rural Chinese migrant workers pour into Chongqing alone every year, making it the world’s biggest city—and building site—fuelling China’s growth engine, even if somewhat less vigorously since the global financial downturn. Long term forecasts suggest another 350 million rural villagers will converge on industrializing cities in China alone by 2025; some pulled by new opportunities, others pushed by poverty and food shortages caused, in part, by the climatic disruptions of global warming.
For Mr Tan, the lure of Chongqing is, in his words, “the big money”. Living in a shed, amid the fine, choking concrete dust and surrounded by hectares of concrete, high rise skeletons, Mr Tan earns 1,000 yuan a month, more than ten times what he eked out of the land and enough to allow him to survive in the city and send money home to the village. His is a familiar tale of aspiration.
But, on Mr Tan’s building site, a number of the world’s most intractable and emerging health threats are converging. Just as the advances of the Industrial Revolution came at a cost to the millions who left the land for Europe’s factories and slums, the very jobs which have pulled hundreds of millions out of abject poverty in the late twentieth and early twenty-first centuries also come with new risks.
For the world’s marginalized communities, economic globalization often means less job security in itinerant industrial and labouring jobs and new toxic threats and accident risks at work. In urban shanty towns, inadequate sanitation and services combined with crowded living conditions greatly increases health risks and vulnerability to communicable diseases.
Then, there are new emerging threats, unique to our times. In Chongqing, and many cities like it, armies of male migrant labourers are cut adrift from village social structures for months and years at a time. With the erosion of social cohesion, high risk lifestyles of cheap sex and drugs can follow; undermining economic gains and threatening the transmission of HIV/AIDS and serious related infections such as drug-resistant tuberculosis.
At the same time rising population mobility resulting from mass travel facilitated by modern transport networks, migration and forced population displacement are providing unprecedented opportunities for the transmission of many communicable diseases—nationally and globally—greatly jeopardizing the health of people on the move and elevating the risk of pandemics.
And, that’s before we consider the health impacts of environmental degradation caused by rapid development. In the world’s industrializing cities, air and water pollution routinely exceed safe levels, exposing tens of millions of people to respiratory risks and diverting meagre family incomes to purchasing safe drinking water. In many poor rural areas, large scale deforestation and resource stripping has led to devastating soil erosion, water shortages and contamination.
Single Biggest Threat
Less immediately apparent, but potentially the single biggest health threat this century, is climate change. This is no longer an abstract notion. We know climatic variations—particularly the droughts and floods which are disrupting agriculture and extreme weather events which in turn damage infrastructure—are hitting vulnerable developing nations the hardest, and will wreak havoc on the world’s poorest people in the coming decades.
China’s official news agency, Xinhau, reported sustained extreme heat in Chongqing in September 2009, as well as water shortages affecting hundreds of thousands of people in the city. Without the resources to “adapt”, such as air-conditioning, low-paid workers toiling outdoors and living under baking, tin roofs are exposed to health threats posed by intense heat and pollution. In surrounding rural areas, livestock and crops are suffering, pushing more farmers off the land.
As early as 2000, the World Health Organization attributed 2.4 per cent of worldwide diarrhoea and 6 per cent of malaria cases to climate change. The first large scale, quantifiable impacts on human health are likely to be changes to the geographic range and seasonality of some infectious diseases, including vector-borne infections such as malaria and dengue fever and food-borne infections such as salmonellosis, which peak in warmer months. We have also begun to identify as “climate change casualties” the victims of extreme weather events, such as the 27,000 deaths associated with abnormally high temperatures in the European summer of 2003.
However, the future public health consequences loom even larger. Much attention is focused on rising sea levels and areas which face inundation—a situation which could drive mass people movements. But, what of the wider scale disruption to food production with changing rainfall patterns, including longer droughts and more intense floods, and the consequent economic losses and food shortages forcing mass migration and exacerbating civil strife?
The “World Development Report 2010: Development and Climate Change”, released in advance of the UN Climate Change Conference in Copenhagen in December 2009, cites evidence that global warming of 2˚C above pre-industrial temperatures could, for example, result in permanent reductions in annual per capita consumption of 4 to 5 per cent in Africa, already the world’s most vulnerable continent.
Climate variability is a feature of Africa’s history, but the frequency and severity of both floods and droughts have increased sharply in recent years, and climate projections indicate that this trend will intensify. This is likely to have devastating consequences for rain-fed agriculture, which employs about 70 per cent of Africa’s population, the report says.
An earlier World Bank report notes; “[the world’s] poor communities will be especially vulnerable. They tend to have limited adaptive capacities and are much more dependent on climate-sensitive resources such as local water and food supplies.” The Intergovernmental Panel on Climate Change has estimated that between 75 and 250 million people will be exposed to increased water stress due to climate change by 2020, most of them in poor countries already facing multiple health challenges.
At the same time, the world is facing a food crisis driven by multiple causes, including climate variability and market distortions. During early 2008, international prices of all major food commodities reached their highest levels in almost 50 years; pushing world hunger through the one billion mark. The global financial downturn since threatens to plunge 55 to 90 million more people into poverty this year alone, according to the United Nations.
From a global health perspective, the growing diversity and magnitude of health-related crises around the world is converging into a potentially disastrous perfect storm.
Towards A More Habitable Homeland