Adapting Communications to Best Inform Vulnerable Groups

As global climate change increases the likelihood of extreme heat events, the Montreal Public Health Department is taking action to ensure that the most vulnerable members of its community remain informed on the best actions that they can take to stay safe during a heatwave. The Department has been active in preparing for extreme heat events from some time. At least as far back as 1994, Montreal had an interest in informing its citizens about the dangers of extreme heat, publishing brochures about ways to stay cool during a heatwave. Over time, the Department came to realize that many people either had difficulty accessing the information or difficulty in implementing the recommendations. They found that the two groups of highest risk for heat related mortality and morbidity were also the same groups that had difficulty accessing the information: the elderly and those suffering from mental illness or addiction. As a result, the Department embarked on a strategy of refining its communication means to help better access these groups.

Understanding and Assessing Impacts

Extreme heat, especially over prolonged periods of time, can have severe negative effects on a person’s health. Furthermore, the most physiologically vulnerable groups of people are the elderly and those struggling with mental illnesses and addiction. Following the death due heat stroke to heat of a local forestry worker in 1994, the Montreal Public Health Department embarked on a program to inform its citizens about the dangers of heat stroke and some means to combat it. This was achieved mainly through the dissemination of brochures on the matter. This program was later refined in 2002 when the Public Health Department conducted its first structure heat-awareness campaign. The 2003 European Heatwave that resulted in over 35,000 deaths galvanized Montreal to create its first official heat-response plan. This plan was then revised in 2007. In 2010, Montreal experienced a 5-day heatwave that elevated the plan into the active intervention stage, prompting the deployment of cooling centres across the city and an aggressive communications campaign. The effectiveness of this program was closely monitored and it was found that often the parents, friends, and loved ones of people suffering from mental health issues were often unaware of the heightened risks this group faces. It was decided then to tailor the communications to specific groups in the hopes of achieving a more widespread awareness of the unique needs of different groups in the face of extreme heat.

Identifying Actions

The current incarnation of the Heat Response Plan comes after many years of review and iteration. The major review conducted in 2007 found that several key demographics were having difficulty accessing the information or putting it into action. As a response, the Montreal Public Health Department modified its communication strategy to more effectively target individual groups. The Public Health Department used focus groups and surveys to help better understand what barriers existed to communication and implementation and what actions could be taken to overcome these barriers. It was also noted that collaboration with a wide range of groups is essential in order to be able produce and disseminate an effective plan; some of those groups including in the collaboration and consultation phase were various municipal departments, regional stakeholders, and neighbouring communities. Additionally, some respondents indicated that the onus was on the Public Health Department to take the lead, with many partners wanting to contribute but expecting the health authority to take a clear and structured lead. Another point of consideration was how long-term development plans affected the health outcomes of citizens in a heat event. If a community has an aggressive tree planting program, for example, its citizens may be more protected from heat stress than a community that did not undertake such a program.


While the elderly and those suffering from mental illness or addiction were the most vulnerable, they were not the only group selected for specific messaging. For example, one of the other groups with targeted messaging was professionals who have small children at home. Even though many of these groups were receiving the same basic information (drink water, rest in air-conditioned areas, reduce physical activity), the wording and imagery would be tailored to better capture the attention of, and convey information to, distinct groups. Taking the example of working professionals with young children, there were specific posters and brochures created that heavily featured imagery of children in order to get their attention. Furthermore, it was determined that not all suggestions are feasible for all populations. People with reduced mobility, for example, may find it difficult to take shelter in an air-conditioned area. Specific messaging was sent to groups like this, with solution tailored to their specific needs. Following a 2010 review of the heat plan, it was found that the messaging targeting individuals with mental health issues was still insufficient. As a result, the Public Health Department began to collaborate with social services centre, community organizations and psychiatric hospitals to ensure better care and coverage for this demographic.

Outcomes and Monitoring Progress

Despite these precautions, it was not possible to prevent all excess deaths from a heatwave. It is often difficult to determine exactly whether or not a person died as a result of heat stress during an extreme heat event. One method that attempts to determine the fatalities of such an event is comparing the death rate during a heatwave to the usual amount of deaths during the same time frame while not under an extreme heat event and counting the difference as ‘excess deaths’ attributable to the heat stress. A report following the 2010 heatwave in Montreal found that the city experience 106 excess deaths during this period of extreme heat. However, that same report noted that the number of excess deaths was lower than it would be in the absence of the measures taken and that the Heat Response Plan was effective in lower rates of mortality and morbidity (see ‘resources’ for more information).