Vulnerabilities - Overview

Direct consequences of climate change for human health in Belgium are a higher vulnerability to heat stress in case of extremely hot summers and the probability of large numbers of casualties in a single flood episode (1).

Indirect consequences of climate change for human health are a.o.: vector-transmitted diseases (malaria, dengue, West Nile virus); increase in Lyme disease; diseases linked to air quality; allergies (increase in hay fever (likely); increase in water-related diseases; increase in food-related diseases; increased exposure to UV-related disorders (1). 

Besides,  a number of indirect health effects may result from climate change due to a deterioration of socioeconomic circumstances (employment, prosperity) and the migration of people (1)

Vulnerabilities - Heat stress

Heat waves combined with urban heat islands (9) can result in large death tolls with the elderly, the unwell, the socially isolated, and outdoor workers (10) being especially vulnerable. Heat waves thus pose a future challenge for major cities (11). Projected heat stress increase toward the mid-21st century is twice as large in cities compared to their surrounding rural areas (22); cities experience a heat stress multiplication by a factor 1.4 to 15 depending on the scenario of climate change. 

The probability of severe heat waves is expected to rise significantly. This is both a consequence of higher mean temperatures and increased variability. Projections for the end of the 21st century show that roughly every second summer could be as warm or warmer (and as dry or dryer) than the summer of 2003 (2).

In Belgium, the heat wave of the summer of 2003 does not seem to have had health consequences as severe and difficult to manage as those in the French cities of Paris and Lyon, the most heavily affected. However, the number of deaths in excess of the mean has been estimated at about 1,300 in the 65 and older age group, equivalent to +19 % deaths during the first weeks of August (3).

Problems caused by prolonged exposure to heat include exhaustion due to sweating, causing water and salt deficiencies, and heat stroke caused by loss of temperature control in the body, a severe condition that can rapidly cause death. The most vulnerable groups are babies and young children, along with elderly people and top class sportsmen and women (2).

The heat wave of August 2003 was probably the most severe observed in Belgium. Part of its impact is thus connected with the limited experience of such events in the country, but we anticipate that climate change may cause such heat waves every other summer by the end of the century (2).

Vulnerabilities - Cold stress

Most European countries have between 5 and 30 % higher death rates in winter than in summer. Winter‑related mortality in many European populations has declined since the 1950s (5). Cold days, cold nights and frost days have become rarer, but explain only a small part of this reduction: improved home heating, better general health and improved prevention and treatment of winter infections have played a more significant role (6).

Vulnerabilities - Food poisoning

High temperatures favor the spreading of certain micro-organisms such as Salmonella and fungus that produce carcinogenic aflatoxine at the surface of cereal (1).

Vulnerabilities - Tick-borne diseases

The number of cases of Lyme disease increased rapidly during the last decade in Belgium, from under 100 to almost 1,000 per year. Ticks are responsible for the transmission of this disease, which leads to a severe condition affecting the skin, heart, nervous system, eyes, kidney and liver (1,2).

It is not yet certain that the increased prevalence of the disease is significantly linked with climate change. No specific studies are available as yet on this topic but a study conducted in Sweden shows that mild winters with increased daily minimum temperature are correlated with higher numbers of ticks. Climate change may thus play a role in the rise in number of people affected, and this trend is likely to continue in the future (1,2).

Vulnerabilities - Mosquito-borne diseases

While climatic factors may favor autochthonous transmission, increased vector density, and accelerated parasite development, other factors (socioeconomic, building codes, land use, treatment, etc) limit the likelihood of climate related re-emergence of malaria in Europe (7).

Vulnerabilities - Sand-fly-borne diseases

Leishmaniasis is a protozoan parasitic infection caused by Leishmania infantum that is transmitted to human beings through the bite of an infected female sandfly. Sandfly distribution in Europe is south of latitude 45⁰N and less than 800 m above sea level, although it has recently expanded as high as 49⁰N. Currently, sandfly vectors have a substantially wider range than that of L infantum, and imported cases of infected dogs are common in central and northern Europe. Once conditions make transmission suitable in northern latitudes, these imported cases could act as plentiful source of infections, permitting the development of new endemic foci. Conversely, if climatic conditions become too hot and dry for vector survival, the disease may disappear in southern latitudes. Thus, complex climatic and environmental changes (such as land use) will continue to shift the dispersal of leishmaniasis in Europe (7).

Vulnerabilities- Air quality

The changes in temperature and humidity affect air quality: the warmth stimulates the forming of ozone and the smog lengthens the allergenic pollen season (1).

Vulnerabilities - Floods

Floods are the most common natural disaster in Europe. The adverse human health consequences of flooding are complex and far-reaching: these include drowning, injuries, and an increased incidence of common mental disorders. Anxiety and depression may last for months and possibly even years after the flood event and so the true health burden is rarely appreciated (8).

Effects of floods on communicable diseases appear relatively infrequent in Europe. The vulnerability of a person or group is defined in terms of their capacity to anticipate, cope with, resist and recover from the impact of a natural hazard. Determining vulnerability is a major challenge. Vulnerable groups within communities to the health impacts of flooding are the elderly, disabled, children, women, ethnic minorities, and those on low incomes (8).

Adaptation strategies - Belgium

As a first step towards adaptation, the federal government, with collaboration at regional and community level, has set up a ‘heat waves and ozone plan‘ in framework of the national environment health action plan (4). This plan introduces a series of phased-in measures and communication initiatives in addition to actions targeting the reduction of ozone formation.

The first phase takes place every summer and focuses mainly on preparatory actions and public information, and calls for solidarity with people at risk. The pre-alert phase begins when the mean minimum and maximum temperatures, over a period of two consecutive days, exceed a threshold corresponding to the 95th percentile of summer temperatures. The alert phase is declared when a heat wave of three days or more is forecast by the Royal Institute of Meteorology or ozone concentrations above the EU information threshold are forecast by the Interregional Environment Unit (2).

Warnings are sent to emergency and geriatric departments of hospitals, rest homes, etc. A survey on the application of measures in these organizations is being conducted. This monitoring is one of the elements taken into account by the authorities when deciding whether it is necessary to move into the crisis phase, which implies the creation of a crisis unit and additional measures, e.g. in hospitals. Since 2007, the working group has widened the scope of its remit to include air pollution episodes affecting human health (2).

Another type of adaptation to heat waves is the structural protection of buildings: thermal insulation, solar protection via shutters, ventilation, etc. … The Brussels region offers a 20% subsidy (up to a maximum of 400 EUR) of the cost of installing an external solar protection system (2).

Adaptation strategies - General - Heatwaves

The outcomes from the two European heat waves of 2003 and 2006 have been summarized by the IPCC (12) and are summarized below. They include public health approaches to reducing exposure, assessing heat mortality, communication and education, and adapting the urban infrastructure.

1. Public health approaches to reducing exposure

A common public health approach to reducing exposure is the Heat Warning System (HWS) or Heat Action Response System. The four components of the latter include an alert protocol, community response plan, communication plan, and evaluation plan (13). The HWS is represented by the multiple dimensions of the EuroHeat plan, such as a lead agency to coordinate the alert, an alert system, an information outreach plan, long-term infrastructural planning, and preparedness actions for the health care system (14).

The European Network of Meteorological Services has created Meteoalarm as a way to coordinate warnings and to differentiate them across regions (15). There are a range of approaches used to trigger alerts and a range of response measures implemented once an alert has been triggered. In some cases, departments of emergency management lead the endeavor, while in others public health-related agencies are most responsible (16).

2. Assessing heat mortality

Assessing excess mortality is the most widely used means of assessing the health impact of heat-related extreme events.

3. Communication and education

One particularly difficult aspect of heat preparedness is communicating risk. In many locations populations are unaware of their risk and heat wave warning systems go largely unheeded (17). Some evidence has even shown that top-down educational messages do not result in appropriate resultant actions (18).

More generally, research shows that communication about heat preparedness centered on engaging with communities results in increased awareness compared with top-down messages (19).

4. Adapting the urban infrastructure

Several types of infrastructural measures can be taken to prevent negative outcomes of heat-related extreme events. Models suggest that significant reductions in heat-related illness would result from land use modifications that increase albedo, proportion of vegetative cover, thermal conductivity, and emissivity in urban areas (20). Reducing energy consumption in buildings can improve resilience, since localized systems are less dependent on vulnerable energy infrastructure. In addition, by better insulating residential dwellings, people would suffer less effect from heat hazards. Financial incentives have been tested in some countries as a means to increase energy efficiency by supporting those who are insulating their homes. Urban greening can also reduce temperatures, protecting local populations and reducing energy demands (21).

Several adaptation measures help to reduce temperatures on a hot day: vegetation, water bodies, modifying urban form (e.g., street orientation), alternative materials (e.g., high-albedo materials), and lowering anthropogenic heat (e.g., lowering the number of cars). Vegetation in urban areas is one of the most investigated adaptation measures, and includes green roofs, green walls, street trees and urban parks (23). The cooling effect of parks is not necessarily limited to the park area, but can be convected away from the park in the direction of the wind, cooling the park surroundings. This effect was studied for an urban park in the city center of Antwerp, Belgium. This triangular park has a southern edge of 500 m long whereas the other two edges are approximately 550 m long. The park is mainly composed of trees, grass fields, walking paths and a pond. The results show a daytime cooling effect of the park on a summer day of 3.4°C. The cooling effect persisted up to 500 m away from the park (23).

References

The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Belgium.

1. Van Ypersele and Marbaix (2004)
2. Ministry for Social Affairs, Health and Environment (2009)
3. Sartor (2004), in: Ministry for Social Affairs, Health and Environment (2009)
4. www.nehap.be
5. Kunst et al. (1991); Lerchl (1998); Carson et al. (2006), in: EEA, JRC and WHO (2008)
6. Carson et al. (2006), in: EEA, JRC and WHO (2008)
7. Semenza and Menne (2009)
8. Hajat et al. (2003)
9. Basara et al. (2010); Tan et al. (2010), in: IPCC (2012)
10. Maloney and Forbes (2011), in: IPCC (2012)
11. Endlicher et al. (2008); Bacciniet al. (2011), both in: IPCC (2012)
12. IPCC (2012)
13. Health Canada (2010), in: IPCC (2012)
14. WHO (2007), in: IPCC (2012)
15. Bartzokas et al. (2010), in: IPCC (2012)
16. McCormick (2010b), in: IPCC (2012)
17. Luber and McGeehin (2008), in: IPCC (2012)
18. Semenza et al. (2008)), in: IPCC (2012)
19. Smoyer-Tomic and Rainham (2001), in: IPCC (2012)
20. Yip et al. (2008); Silva et al. (2010), both in: IPCC (2012)
21. Akbari et al. (2001), in: IPCC (2012)
22. Wouters et al. (2017)
23. Toparlar et al. (2017)