The effects of heatwaves on health in Europe have been investigated in a number of studies. An increase in mortality and years of life lost in European cities during the nineties has been observed, even after adjusting for the harvesting effect [1
]. A main risk group for mortality consists of elderly people [2
]. Although there is little evidence that directly describes the impact of heat on socially isolated individuals, including homeless people, they are considered a risk group due to the lack of social control and a relatively high proportion of morbidities. It was estimated that, due to the very severe heatwave in 2003 in Western Europe, between 1400 and 2200 individuals died in The Netherlands [3
], and more than 70,000 in Europe [4
]. Apart from mortality, heatwaves have a considerable impact on morbidity. Mastrangelo et al. reported an increase in respiratory diseases and heat diseases during heatwaves, but no increase in circulatory diseases [5
]. Amongst the elderly, an increase in heat-related symptoms, such as fatigue, sleep disturbance and annoyance due to heat, was shown in a recent study by van Loenhout et al. as a consequence of increasing indoor temperatures [6
]. Due to climate change, there is an expected increase in heatwaves in Western Europe, both in frequency and intensity [7
The severe heatwave that hit Europe in 2003 prompted many countries to implement heatwave early warning systems with response plans [8
]. These heatwave plans usually feature timely accurate warnings, tailored communications and notifications of adaptation actions to the most vulnerable populations and heat avoidance advice to general populations [9
]. The main aim of the heatwave plans is to reduce the avoidable public health consequences of heatwaves. A study in the Florentine area (Italy) showed a general reduction in heat-related mortality from the four years before 2003 to the four years after 2003 in elderly (≥75 years) people [10
]. In addition, a French study showed that mortality during a 2006 heatwave was lower than predicted by a model, which could partially be due to the introduction of a heat warning system [11
]. A systematic review from 2014 looked at studies that assessed the impact of heat prevention plans and climate adaptation strategies, and found a reduction of adverse effects during extreme heat in places where preventive measures have been implemented [12
]. In contrast, a recent study on heat-related mortality in nine European cities before and after the 2003 heatwave showed that improvement in adaptation was achieved by only a third of these cities, and two of these worsened their adaptation capacity while the other one remained unchanged [13
Both Belgium and The Netherlands have developed national plans in 2005 and 2007, respectively, as public health measures against heatwaves [6
]. In the Belgian region of Wallonia, a recent survey assessed the familiarity of stakeholders and end users with protection and adaptation measures to heat. However, no specific assessment of local implementation was undertaken [15
]. Since the successful implementation of a national heatwave plan locally depends largely on the participation and collaboration of relevant stakeholders, we interviewed key informants from those organisations with the aim of assessing their perceptions on the heatwave plans in terms of responsibilities, partnerships, and effectiveness of the local implementation in Brussels and Amsterdam.
The most striking finding was the mismatch between the intended and the actual familiarity with the national heatwave plans among the care organisations under study. Even though elderly care institutes, homecare organisations and hospitals were listed in the national heatwave plans of both countries, representatives from these organisations were not aware of the existence of the plan, and did not receive alerts during a hot period. Additionally, among all respondents, care organisations gave the lowest priority to heatwaves. Both findings are consistent with a UK study, where a large majority of care organisations in London were not familiar with the national heatwave plan, even though these organisations were specifically mentioned in the Heatwave Plan for England [19
], and the majority of these respondents did not regard heatwaves as high priority [20
]. A study among care institutions in Amsterdam, which showed that less than 10% of the residents’ rooms in these institutions had air conditioning, suggests that heat is not considered an important factor for the health of this vulnerable population [21
]. As care organisations have the closest contact with at-risk populations out of all the stakeholders, this low priority brings about a dilemma. Based on our findings, awareness of the impact of heat on health among stakeholders working in these types of organisations should be urgently addressed.
It became apparent that several risk groups for heat are not sufficiently addressed by the national heatwave plans. Homeless people in The Netherlands fall under the responsibility of the municipality, but in Belgium there is no governmental organisation responsible for them. However, homeless people are a risk group due to them having poorly controlled chronic diseases, respiratory diseases and mental illnesses, which render them vulnerable [22
]. One stakeholder pointed out that individuals with little social contact do not receive enough attention in the national heatwave plan, and a survey held in the Wallonia region in Belgium came to a similar conclusion [15
]. There is a discrepancy between the risk groups being targeted among the two municipalities in Belgium in our study: one targets all risk groups mentioned in the national heatwave plan, while the other focuses only on the elderly. We believe that there should be more emphasis on the variety of risk groups for heat, such as socially isolated individuals, and the organisational structures responsible for their care.
Although most stakeholders welcome the national heatwave plan, since it describes the different stakeholders and provides information on heat and health, it is considered a general weakness that the roles and responsibilities are not clearly described. Stakeholders can decide not to undertake any actions, since none of the intended actions is enforced by law. Although it is a conscious decision by the activators not to assign responsibilities, there is no consensus among the stakeholders that this is the best approach. The lack of contact between different stakeholders was also mentioned as a weakness by key informants from each country. We recommend the involvement of representatives from relevant stakeholders for a more effective uptake, as recent research suggests [15
In Belgium, implementation on a local level is not included in the national plan, and should be taken up fully by the local stakeholders. Similarly, a previous study showed that the UK National Heatwave Plan, although considered an important source of disaster risk knowledge, was not successful in steering sustainable change in the way that heat risk is planned for at the local level [23
]. This results in large variation in the number of activities between different municipalities, as was observed in our study. Sharing best practices and lessons learnt about implementation at a local level could be useful. For example, the municipality of Etterbeek had developed a very comprehensive local heatwave plan, in which they raised awareness towards risk groups, established a contact point for the general public and provided information to professionals. Lessons can be learnt from these pioneering municipalities by others. There is also a need for more detailed studies, describing the effectiveness of local heatwave plans in averting local excess mortality. Recent research has found no real adaptation to heat between the 2003 and 2007 heatwaves [13
]. As this study shows, there is a substantial room for improvement in terms of local implementation of national heatwave plans, since these plans have a potential to improve adaptation to heat and heatwaves. The question then remains how well both countries are prepared to react to the next heatwave. As evaluation remains one of the largest gaps in research [12
], this question is difficult to answer. However, this study does provide early insights into professional organisations that seem to be unaware of heat and its health impact, even though they tended to be those closest to the most vulnerable. This study uncovers the reality that information does not flow downstream and this might be an extraordinary source to avert morbidity and mortality in the future. To achieve this, we encourage local studies to be undertaken, which should include surveillance and evaluation.
Our study does not give a complete overview on national heatwave plan perception in Brussels and Amsterdam, since only one or few key informants were interviewed for each type of organisation. Therefore, the results should be considered as indicative of the general situation. We did not get any insight into the extent of general practitioners and childcare centres that receive a heat warning or act after receiving it. The fact that we never received a reply from these organisations from either country could imply that they do not see this topic as a priority or simply have little knowledge about it.
Due to differences between our two studied countries, the responsibilities of parallel organisations might differ, e.g., the local/regional implementation of the national heatwave plan in Belgium is coordinated by the municipality, while in The Netherlands this falls under the responsibility of the Municipal Health Organisation. Therefore, a valid comparison of national heatwave plan perception between the two countries is not always possible. However, we would still encourage Belgium and The Netherlands to collaborate, e.g., by streamlining the phases and activation criteria for the national heatwave plans.