Climate change and population health – lessons from the 19th century

Professor Emeritus Anthony McMichael AO

There are population health lessons from the mid-nineteenth century response to the rampant sickness, epidemic disease and increased death rates associated with the big, new and growing industrial cities. The subsequent great gains in human safety and health came from transformative legislation and social action. Today, we should be seeking to achieve similar transformative changes to deal with the population health challenges of climate change.

Among the several major and historically unprecedented global environmental changes that human pressures have caused, the climate system is the most likely source of acute shocks/emergencies within the coming decade.

Now, at last, as Australians and their policy-makers are beginning to perceive that the impacts of unabated climate change include impacts within the human system. Consideration of risks to the safety, health and survival of communities are entering the discourse. That crucial dimension has long been a paradoxical blind spot, a wavelength of relative ignorance. This recognition of risks to humans per se come about substantially, because of a growing understanding of the contributory, amplifying, role that underlying climate change plays in the increasing frequency and intensity of many categories of extreme weather events.

Climate change is no simple ‘risk factor’ for illness like smoking, alcohol abuse or not wearing one’s seat-belt. Nor are its health impacts restricted to the high-risk individuals. Its impacts impinge, via many paths, on whole communities. In that broader population health domain, there are appropriate lessons from the mid-nineteenth century response to the unintended negative consequences of population concentrations associated with rapid industrialisation.

The challenge was to deal with the rampant sickness, epidemic disease and increased death rates in the big new and growing industrial cities. The subsequent great gains in human safety and health came from transformative legislation and social action. Biomedical knowledge and intervention (really only available to the rich anyway) was limited and of dubious value. England provides the best documented examples: the installation of a huge sewer system in London (and elsewhere), legislation to curb factory smoke emissions, empirical knowledge (pre-germ theory) of the benefit of household and neighbourhood hygiene, filtration of reticulated water, and stricter food safety laws and monitoring. Quarantine in ports (though opposed by free traders) was introduced in response to the pandemics of cholera that swept through Europe in the 1830s and 1850s.

Today, motivated by recognition of the community-wide and long-term risks to the health and survival of populations, we should be seeking to achieve similar transformative changes in our (often carbon-intensive) technologies, economic priorities, and how we construe, measure and monitor human wellbeing and health, particularly at the collective levels of community or population.

Professor McMichael was a contributor to the Australia21 publication Placing global Change on the Australian election agenda released in June. Here is a link to his latest piece Why climate change should be a key health issue this election