Abstract. McMichael AJ, Lindgren E (The Australian National University, Canberra, Australia; and Karolinska Institute, Stockholm, Sweden). Climate change: present and future risks to health: and necessary responses (Review). J Intern Med 2011; doi: 10.1111/j.1365-2796.2011.02415.x. Recent observed changes in Earth's climate, to which humans have contributed substantially, are affecting various health outcomes. These include altered distributions of some infectious disease vectors (ticks at high latitudes, malaria mosquitoes at high altitudes), and an uptrend in extreme weather events and associated deaths, injuries and other health outcomes. Future climate change, if unchecked, will have increasing, mostly adverse, health impacts - both direct and indirect. Climate change will amplify health problems in vulnerable regions, influence infectious disease emergence, affect food yields and nutrition, increase risks of climate-related disasters and impair mental health. The health sector should assist society understand the risks to health and the needed responses.