Polyepidemic: A Looming Threat in the Era of Climate Change
August 7, 2023
When we speak of climate change, the conversation is often coloured by tales of melting ice caps, extreme weather events and rising sea levels. But beneath the surface lurks a more insidious threat, one that we’ve so far given insufficient attention to the impending reality of polyepidemics — the concurrent outbreak of multiple epidemics.
The term ‘polyepidemic’ conjures an intimidating tableau, a future where health systems grapple with individual health crises and an entangled web of them. As climate change intensifies, this previously nebulous fear is hardening into a disturbing possibility. Outgoing CEO of Gavi, the Vaccine Alliance, Seth Berkley, recently spelled out this reality, warning of “massive movement of people, water challenges, desertification, displaced people…” all leading to increased disease, spurred on by the disruption of ecosystems.
Climate change is far more than a mere readjustment of global temperature; it reconfigures the fabric of our ecosystems and societal structures, thereby amplifying disease risks. The triggers for this amplification lie in the shifting behaviours of disease vectors and our increasing encroachment on their habitats.
Altered climatic conditions are redefining the geographical reach of disease-carrying organisms such as mosquitoes, heralding a potential surge in illnesses like malaria and dengue. But this is just the tip of the ecological iceberg.
Even slight disruptions to ecosystems can create chain reactions of profound consequence. As human intrusion into natural habitats escalates, so does our exposure to wildlife and the threat of zoonotic diseases — those that jump from animals to humans. Ebola, Zika, and the catastrophic COVID-19 pandemic are harbingers of this rising menace.
The climate crisis also exacerbates conditions conducive to disease spread. Increased frequency of extreme weather events like floods and droughts foster optimal conditions for disease vectors and displace human populations, often corralling them into unsanitary conditions ripe for disease spread.
Furthermore, climate change intensifies chronic water scarcity and accelerates desertification. Changes in temperature and precipitation patterns threaten to morph swathes of our planet into uninhabitable wastelands, triggering mass displacement and migration. This, in turn, places enormous strain on healthcare systems, fostering conditions for rampant disease transmission — the making of a polyepidemic landscape.
But the ramifications of a polyepidemic scenario reach beyond health. Such a scenario risks deepening socio-economic inequalities, as epidemics and climate change disproportionately affect vulnerable and marginalised communities. This lethal cocktail of disease and climate change threatens to entrench these groups in a relentless cycle of poverty and illness, undoing decades of progress in global health and development.
Tackling the spectre of a polyepidemic future requires a comprehensive, integrative strategy. At the heart of this lies our battle against climate change. By curbing greenhouse gas emissions and halting global warming, we can dampen some environmental disruptions that fan the polyepidemic flames. Simultaneously, it is vital to strengthen our public health systems and deepen our understanding of the intricate interplay between climate change and disease dynamics.
The spectre of a polyepidemic world, moulded by climate change, exposes the alarming convergence of our environmental, health, and societal issues. It is a powerful wake-up call that climate change is not a distant, unrelated crisis but an immediate threat necessitating urgent, comprehensive, and collective action.