Climate change is a health issue, not just an environmental one. Rising heat, shifting rainfall, and more extreme weather are already harming human health, and the risks will grow.
Heat is the most direct threat. Heatwaves cause heat stroke and worsen heart and lung disease, with older adults at highest risk. Floods and storms injure people, damage hospitals, and spread waterborne disease. Changing temperatures also shift where mosquitoes and other disease carriers can live, which affects diseases like malaria.
The World Health Organization expects climate change to cause about 250,000 additional deaths per year between 2030 and 2050, from malnutrition, malaria, diarrhea, and heat stress. WHO also estimates the direct damage costs to health at 2 to 4 billion US dollars per year by 2030.
Poorer countries face the worst of it. They have weaker health systems and fewer resources to adapt, even though they contributed least to the problem. Within every country, children, older adults, and people with chronic illness are most vulnerable.
Cutting emissions helps health directly. Cleaner transport, energy, and food systems reduce air pollution, which saves lives now. Adaptation matters too: heat warning systems, stronger clinics, and disease surveillance all reduce harm.
Students interested in this field can explore public health careers and their impact or ways to support public health in your community. For how island nations face these risks, see Tuvalu’s climate adaptation efforts.

