Preventing the extreme consequences of extreme heat

Studies show that exposure to extreme heat can exacerbate or lead to a range of serious health issues, including heat exhaustion, heat stroke, or even death. Climate change is leading to more extremely hot days all across the world, including in Canada. In fact, the World Health Organization (WHO) has identified climate change as the biggest threat to human health in the 21st century.

Growing up in a rural eastern Ontario community, Shawn Donaldson has always been interested in the environment. With a mother who was a nurse, he couldn’t help but have an interest in human health. “Ever since I was a child, I have had a deep appreciation of the many ways in which the environment can affect our health.”

During his masters and Ph.D. studies, Donaldson focused on health issues in rural and remote communities in Canada, working closely with Indigenous communities. He has led health research in the circumpolar region, including in the Canadian Arctic.

Recently, Donaldson started working more specifically on the link between climate change and human health at Health Canada. “We know that climate change has a significant impact on human health and that it is an issue that is important to Canadians,” he says.

Health Canada’s Heat Division, part of the Climate Change and Innovation Bureau, focuses on protecting Canadians from extreme heat. Extreme heat events, or “heat waves”, involve high temperatures and sometimes, high humidity. Although the levels of temperature extremes may vary between regions, unusually high heat can have negative impacts on your health.

“One of the most important things to understand about the consequences of extreme heat is that they are preventable,” says Donaldson. “Canadians can take action, but not everyone is aware of what to do and how to protect themselves.”

To address this, the Heat Division team has been working to develop new ways to get this information out to Canadians. The team has developed a range of products (including brochures, infographics, videos and outreach activities) to inform people about the dangers of extreme heat, including heat rash, dehydration, fainting, heat stroke, or even death. Some people may be at higher risk, such as young children, seniors, people living with chronic diseases or mental illness, or people who work or are active outdoors. “By understanding who is most at risk, taking action to keep cool, and watching out for the signs and symptoms of heat illness, Canadians can keep themselves healthy,” says Donaldson.

Health Canada also assists provincial, territorial and municipal health authorities and communities across the country to prepare for extreme heat events through supporting the implementation of Heat Alert and Response Systems (HARS). In the case of extreme heat, HARS helps public health officials, emergency management officials, and community and social service providers prepare for and respond to extreme heat events. HARS typically involves preparing the community for the heat season by identifying their needs and engaging partners.

HARS also includes a heat alert protocol used to warn the public of extreme heat events that could have potential health impacts, a community response plan to guide public health interventions, a communications plan, and an evaluation plan. HARS help to protect Canadians from the adverse health impacts of extreme heat events.

Once a heat warning is issued, people can modify their schedule, stay in a cool place during peak heat hours, wear a sunhat and light-coloured loose-fitting clothing when outdoors, drink water, and check on vulnerable neighbours, friends, and family who may need help. Taking these actions can prevent illnesses and deaths.

Whether it be working with health authorities across the country to implement programs to address heat health risks, or educating Canadians on how they can protect themselves, the Heat Division is committed to protecting the health of Canadians. “I am lucky to work with such a dedicated, professional, and knowledgeable group of people,” says Donaldson.