The Body Count of a Warming World: Climate Change Is Now a Public Health Emergency
We have spent decades debating climate change as an environmental problem. It is time we started treating it as what it has become: the greatest public health crisis of our era.
The numbers are no longer projections. They are body counts. The rate of heat-related mortality has increased 23 percent since the 1990s, pushing total heat-related deaths to an average of 546,000 per year. In 2024, a record-high 154,000 people died from wildfire smoke-derived air pollution alone. Air pollution now causes 7 million deaths a year — one in every nine deaths worldwide. And these are not distant projections. They are happening now, in real time, in every country on earth — including Pakistan.
The Heat That Kills Quietly
Heatwaves are what scientists call the silent killer. They disproportionately affect older people — sustained night-time temperatures are the primary cause of death because while sleeping, older people are unable to consciously regulate their body temperature. The average person was exposed to 16 days of dangerous heat in 2024 that would not have been expected without climate change, with infants and older adults facing over 20 heatwave days per person — a fourfold increase over the last twenty years.
Recent research attributes 37 percent of all heat-related deaths to human-induced climate change. That is not a natural disaster. That is a policy failure — measurable, attributable, and preventable.
The economic consequences compound the human ones. Heat exposure caused a global loss of $1.09 trillion in labour capacity in 2024 alone. For countries like Pakistan — where outdoor labour in agriculture, construction, and transport sustains millions of livelihoods — extreme heat does not just kill. It quietly dismantles the economic foundations of entire communities.
The Return of Diseases We Thought We Were Containing
Climate change is expanding the climate niche that supports mosquitoes carrying dengue and other infectious diseases. The transmission potential for dengue by its two main mosquito vectors increased by 48.5 percent from the 1950s to 2015–2024, contributing to the 7.6 million dengue cases reported globally in early 2024.
This is not a coincidence. It is a consequence. As temperatures rise, the geographic range of disease-carrying vectors expands into regions previously considered safe. The mosquito that spreads dengue fever, previously limited to tropical environments, has now been found as far north as San Francisco and Washington DC, with locally transmitted cases recorded in California, Arizona, Florida, and Texas.
Without preventive actions, deaths from vector-borne diseases — currently over 700,000 annually — may rise significantly. For Pakistan, which has battled dengue outbreaks in Lahore and Karachi with increasing frequency, and where malaria remains endemic in rural and flood-affected areas, this trajectory is not theoretical. It is already visible in every hospital admission record.
The Air We Breathe
Ninety-nine percent of people globally now breathe toxic air. That figure is both a scientific finding and a moral indictment of the choices made by governments and industries over the last century.
Exposure to fossil fuel pollution is associated with an increased risk of heart disease, lung cancer, chronic obstructive pulmonary disease, lower respiratory infections, stroke, type 2 diabetes, and adverse birth outcomes. Every year, more than 8 million people worldwide die prematurely as a result of fossil fuel air pollution.
Failure to transition to clean energy has led to an estimated 2.52 million deaths from fossil fuel-derived outdoor air pollution, and an estimated 2.3 million deaths from dirty fuel-derived household air pollution in 2022 alone. In Pakistan, where millions of households still rely on wood, kerosene, and coal for cooking, and where industrial emissions go largely unregulated, this is not a distant statistic. It is the air inside homes, in schools, in lungs.
The Mental Health Dimension Nobody Talks About
The physical toll of climate change receives most of the attention. The psychological toll remains largely invisible — and it is growing.
Up to half of people exposed to an extreme weather event experience a mental health impact such as anxiety, depression, or PTSD. Children are especially vulnerable to natural disasters, with negative outcomes ranging from missed school and emotional distress to ongoing behavioural problems.
Climate change induces both immediate mental health issues like anxiety and post-traumatic stress, and long-term disorders due to factors like displacement and disrupted social cohesion. In Pakistan, where the 2022 floods displaced 33 million people overnight, the scale of psychological trauma that followed has never been adequately measured — let alone addressed.
The Inequality at the Heart of This Crisis
Climate-sensitive health risks are disproportionately felt by the most vulnerable and disadvantaged, including women, children, ethnic minorities, poor communities, migrants or displaced persons, older populations, and those with underlying health conditions.
This is the central injustice of the climate health crisis: those who have contributed least to the problem bear the greatest burden of its consequences. Low-income and middle-income countries now suffer the most from the health impacts of climate change, despite contributing a fraction of the cumulative emissions that have caused it. Pakistan contributes less than one percent of global greenhouse gas emissions. It absorbs floods, heatwaves, glacial disasters, and disease outbreaks at a rate that no domestic health system can sustainably absorb.
Governments spent $956 billion on net fossil fuel subsidies in 2023 — more than triple the annual amount pledged to support climate-vulnerable countries. Fifteen countries spent more subsidising fossil fuels than on their entire national health budgets. This is the arithmetic of global injustice written in dollars and degrees.
What Must Change
Between 2030 and 2050, climate change is expected to cause approximately 250,000 additional deaths per year from malnutrition, malaria, diarrhoea, and heat stress. These deaths are not inevitable. They are the consequence of choices being made — or not made — right now.
The path forward requires three things. First, climate action must be reframed as health action. Every delayed emission reduction is a deferred death sentence for someone, somewhere — usually someone poor, usually someone in the Global South. Second, health systems in vulnerable countries must be strengthened specifically to manage climate-related illness — not as a charity afterthought, but as a core obligation of international climate finance. Third, the communities absorbing the greatest health burden of this crisis must have a voice in the policy decisions that determine its trajectory.
There were an estimated 160,000 premature deaths avoided every year between 2010 and 2022 from reduced coal-derived air pollution alone. The solutions exist. The evidence is overwhelming. What is missing is the political will to act as if human lives — all of them, not just those in wealthy countries — are worth protecting.
The climate crisis is not coming. It is here. And it is already being counted not in degrees or parts per million, but in the quiet, preventable deaths of people who deserved better from the world they inherited.
The views expressed in this article are solely those of the author and do not necessarily reflect the views of The Opinion Desk.
