Climate change is considered by many to be a the single-most dangerous factor affecting human health

Human activities – particularly the burning of fossil fuels for energy needs – have released large quantities of carbon dioxide and other greenhouse gases into the atmosphere which has led to the heating of the earth's environment.

Climate change has many negative consequences for health. Extreme heat, variable rainfall patterns, and increases in natural disasters and increasing incidence of infectious diseases all affect health detrimentally. Climate change is also creating a wave of environmental migrants and refugees who no longer have viable homes because of the effects of climate change.

All people are affected by climate change; however, some groups face heightened risk. Young people are at particular risk from climate-related health issues because they bear the longest exposure to the effects of climate change. Elderly individuals also face heightened risks because of pre-existing conditions or infirmities. By and large, the effects of climate change will affect people living in countries or areas with limited health infrastructure the most, because of the escalating needs imposed by climate-related health issues.