Sharon E. Straus discusses the urgent need for the upcoming G7 summit to address climate change impacts on health.

__________________________________________

On May 12, 2025, the S7 (the world’s leading science academies) released three statements and recommendations to inform the G7 summit discussions. These recommendations advocate for international collaboration on pressing global issues. They underscore that actions in one country can impact others, whether through war, immigration policies, tariffs, backlash against addressing inequities, infectious diseases, or climate catastrophes.

For the 2025 G7, the statements focus on Advanced Technologies and Data Security, Sustainable Migration and Climate Action and Health Resilience. Widespread changes in the Earth’s climate harm health globally and provide challenges to the resilience of health, public health and social services. We must act now to mitigate risks from the growing health impacts of climate change.

Photo Credit: Pembina Institute/flickr. Image Description: Boreal forest along the Athabasca River.

In Canada, warming is happening at twice the global rate and we experience extreme heat, wildfires, flooding and air pollution. These lead to food and water insecurity, and increases in food-borne illnesses, infectious diseases, chronic diseases and health care utilization amongst other outcomes. For example, the wildfires in 2023 led to increased asthma-related emergency department visits in Ontario. These events strain our stretched health and public health systems.

Some populations are at higher risk of climate change impacts than others. Indigenous communities, especially those living in remote northern areas are particularly vulnerable to the health impacts of climate change. As of May 8, 2025, 38 long-term drinking water advisories were in effect in 36 Indigenous communities. Bill 61, the First Nations Clean Water Act, was introduced in 2023 to affirm self-governance over water, which is a vital step toward climate and health justice. Hopefully our new federal government will push this critical Act to completion.

Other populations who are particularly vulnerable to health effects of climate change include those experiencing homelessness and frail older adults. In Canada, we have a growing number of people who experience homelessness, with concerns this number will grow given current economic threats and uncertainty. There is a rising proportion of people with experience of homelessness aged 50 years and older; they are physiologically 15-20 years older than their housed counterparts and at higher risk of chronic diseases including those exacerbated by climate change. Similarly, frail older adults are at high risk of the health effects of climate change, evident through the impact on those living in long-term care homes with poor air quality and lack of air conditioning during the COVID-19 pandemic.

The S7 statement provides seven recommendations on addressing climate change and health including investing in innovative solutions. In challenging economic times, we cannot ignore the need to invest in innovation such as interventions that promote climate change and health. We need to develop resilient public health and health systems for climate change concerns and address the disproportionate impact of climate change on those populations who are particularly vulnerable. And we must engage the public on these actions; this is critical given widespread disinformation and misinformation.

This is a time for bold, inclusive action. Policy makers, researchers, clinicians, and the public must work together. Our recent federal election was different from the past three federal elections in that climate change discussions were sidelined due to threats from the US against Canadian sovereignty and trade. However, we cannot forget the linkages between climate, health, public health and our economy. Moreover, we cannot depend on “global governance” to tackle this critical issue.

Researchers should play a critical role by pushing innovative, transdisciplinary research. Climate change is a complex issue and requires experts from different fields and with different expertise to come together. This requires us to show scientific humility – a single individual or discipline cannot answer this challenge alone.

Climate change is a health issue and a social justice issue. We must center the health and wellbeing of the population in all actions and policy. Most importantly, if we make things better for those experiencing health disparities, we will make things better for all. Canada must not wait for others to act – we can lead the way.

__________________________________________

Sharon E. Straus is a Professor in the Department of Medicine at the University of Toronto, and Executive Vice President of Clinical Programs, and Chief Medical Officer, Unity Health Toronto.