[…] Until mid-century, projected climate change will impact human health mainly by exacerbating health problems that already exist (very high confidence). Throughout the 21st century, climate change is expected to lead to increases in ill-health in many regions and especially in developing countries with low income, as compared to a baseline without climate change (high confidence). Health impacts include greater likelihood of injury and death due to more intense heat waves and fires, increased risks from food borne and waterborne diseases and loss of work capacity and reduced labor productivity in vulnerable populations (high confidence). Risks of under nutrition in poor regions will increase (high confidence).
https://archive.ipcc.ch/pdf/assessment-report/ar5/syr/SYR_AR5_FINAL_full_wcover.pdf