Health impact of climate change and the role of epidemiology

1. Co-chairs, fellow speakers Dr Fukuda and Dr Gubler, colleagues, friends, ladies and gentlemen, good morning! First of all, I would like to thank the Indian Association of Epidemiologists and the WHO/SEARO for inviting the WHO Centre for Health Development to be here. It is indeed a pleasure and a privilege to be part of the �SEA Regional Conference on Epidemiology� and �Plenary two: Epidemiology: ensuring health security�. I have been tasked this morning to strengthen our knowledge base and understanding of climate change � regarded as an unprecedented challenge for humanity � as it impacts our health, calling for strategic and stronger actions to address the health risks associated with it, as well as to highlight the role of epidemiology in this regard. Co-chairs, fellow speakers Dr Fukuda and Dr Gubler, colleagues, friends, ladies and gentlemen, good morning! First of all, I would like to thank the Indian Association of Epidemiologists and the WHO/SEARO for inviting the WHO Centre for Health Development to be here. It is indeed a pleasure and a privilege to be part of the �SEA Regional Conference on Epidemiology� and �Plenary two: Epidemiology: ensuring health security�. I have been tasked this morning to strengthen our knowledge base and understanding of climate change � regarded as an unprecedented challenge for humanity � as it impacts our health, calling for strategic and stronger actions to address the health risks associated with it, as well as to highlight the role of epidemiology in this regard.

2. Outline of Presentation My objective for this presentation is to answer with you the following 4 questions: 1) What are the impact or risks brought about by climate change?; 2) Who are at risk? 3;) What can be done?; and 4) What is the role of epidemiology?My objective for this presentation is to answer with you the following 4 questions: 1) What are the impact or risks brought about by climate change?; 2) Who are at risk? 3;) What can be done?; and 4) What is the role of epidemiology?

3. Climate change and health impacts This leads us to the broad health impacts of climate change and corollary, the necessary countermeasures. Both our ability to adapt to environmental changes in order to reduce impacts and to implement mitigation measures to reduce GHG emissions are equally important tasks. How does climate change affect health? Key factors that impact on health are environmental conditions, socio-economic conditions and the health system itself. Climate change has a modifying impact on these factors directly, indirectly and causing socio economic disruption as well. Heat waves, extreme weather events such as storms, floods, droughts and cyclones, and air pollution are some direct effects on health. Indirect effects on health are related to vector-borne and water-borne infectious diseases, malnutrition secondary to decreased food production. Loss of property, income and difficulties in rehabilitation have long-term effects such as depression and other stress related mental disorders. The interaction between climate change and the drivers of health produces health impacts that are detrimental to certain groups. This leads us to the broad health impacts of climate change and corollary, the necessary countermeasures. Both our ability to adapt to environmental changes in order to reduce impacts and to implement mitigation measures to reduce GHG emissions are equally important tasks. How does climate change affect health? Key factors that impact on health are environmental conditions, socio-economic conditions and the health system itself. Climate change has a modifying impact on these factors directly, indirectly and causing socio economic disruption as well. Heat waves, extreme weather events such as storms, floods, droughts and cyclones, and air pollution are some direct effects on health. Indirect effects on health are related to vector-borne and water-borne infectious diseases, malnutrition secondary to decreased food production. Loss of property, income and difficulties in rehabilitation have long-term effects such as depression and other stress related mental disorders. The interaction between climate change and the drivers of health produces health impacts that are detrimental to certain groups.

4. Climate change increases health vulnerability Example: Diarrheal Disease Let us look at a specific illustrative example: diarrhea, a water related disease. Independent of any effect of temperature, diarrheal disease will increase in populations without access to safe water and sanitation. To this baseline, add climate parameters such as temperature, humidity and precipitation. The survival and replication of pathogens in the environment and water sources will be altered. These proximal causes contribute to infectious disease hazards, and the outcome is reflected by the increased numbers of cases and deaths attributable to diarrhea. As illustrated in this example, poor coverage of water and sanitation heightens health vulnerability to climate change. Let us look at a specific illustrative example: diarrhea, a water related disease. Independent of any effect of temperature, diarrheal disease will increase in populations without access to safe water and sanitation. To this baseline, add climate parameters such as temperature, humidity and precipitation. The survival and replication of pathogens in the environment and water sources will be altered. These proximal causes contribute to infectious disease hazards, and the outcome is reflected by the increased numbers of cases and deaths attributable to diarrhea. As illustrated in this example, poor coverage of water and sanitation heightens health vulnerability to climate change.

5. Direction and magnitude of change of selected health impacts of climate change Climate change will affect the fundamental determinants of health: food, air, water. What is the direction and magnitude of the health impacts? This diagram is a summary, indicative and not comprehensive and very much semi-quantitative but it gives us a good overview of the health impacts of climate change. First, there are a number of points from this diagram which I would like to highlight: First) There will be some positive outcomes symbolized by blue arrow (for example, reduction of cold related deaths) or both negative and positive impacts. But overwhelmingly, the balance of health effects is on the negative side which is symbolized by red arrows. Secondly, the largest effect, globally, is projected to be from malnutrition which impinges on the MDG target of reducing world hunger by half by 2015. Climate change is projected to increase for example the percentage of the Malian population at risk of hunger from 34% to around 64% and 72% by the 2050s, although this could be substantially reduced by the effective implementation of a range of adaptive strategies (Butt et al., 2005). Climate-change models project that those likely to be adversely affected are the regions already most vulnerable to food insecurity which may lose substantial agricultural land. Overall, climate change is projected to increase the number of people at risk of hunger (FAO, 2005).Climate change will affect the fundamental determinants of health: food, air, water. What is the direction and magnitude of the health impacts? This diagram is a summary, indicative and not comprehensive and very much semi-quantitative but it gives us a good overview of the health impacts of climate change. First, there are a number of points from this diagram which I would like to highlight: First) There will be some positive outcomes symbolized by blue arrow (for example, reduction of cold related deaths) or both negative and positive impacts. But overwhelmingly, the balance of health effects is on the negative side which is symbolized by red arrows. Secondly, the largest effect, globally, is projected to be from malnutrition which impinges on the MDG target of reducing world hunger by half by 2015. Climate change is projected to increase for example the percentage of the Malian population at risk of hunger from 34% to around 64% and 72% by the 2050s, although this could be substantially reduced by the effective implementation of a range of adaptive strategies (Butt et al., 2005). Climate-change models project that those likely to be adversely affected are the regions already most vulnerable to food insecurity which may lose substantial agricultural land. Overall, climate change is projected to increase the number of people at risk of hunger (FAO, 2005).

6. Climate change affects everybody but not in the same way Who is at risk? Climate change will affect everybody but not in the same way. Geography, health system preparedness, health status, age, social class and support systems will make a difference. Specific populations, as you can see here, differ in vulnerability. As growing and developing beings, children are at risk. In the last few decades, the prevalence of allergies among children has increased in Europe for instance as a consequence of an earlier onset of the spring pollen season. The older persons are more vulnerable to heat stress: chronic diseases and drugs can decrease their ability to cope with extreme hot weather. Geographically, populations most at risk are the rural poor and those living in megacities, mountain areas, water-stressed and coastal areas. Knowledge of which groups or geographical areas are most vulnerable to the health impact of climate change allows health systems to target interventions appropriately, in collaboration with other sectors. Who is at risk? Climate change will affect everybody but not in the same way. Geography, health system preparedness, health status, age, social class and support systems will make a difference. Specific populations, as you can see here, differ in vulnerability. As growing and developing beings, children are at risk. In the last few decades, the prevalence of allergies among children has increased in Europe for instance as a consequence of an earlier onset of the spring pollen season. The older persons are more vulnerable to heat stress: chronic diseases and drugs can decrease their ability to cope with extreme hot weather. Geographically, populations most at risk are the rural poor and those living in megacities, mountain areas, water-stressed and coastal areas. Knowledge of which groups or geographical areas are most vulnerable to the health impact of climate change allows health systems to target interventions appropriately, in collaboration with other sectors.

7. The number of patients are recorded in this table from years 2000 to 2007. You may note that the total for year 2007 is 7x higher than that of year 2000.The number of patients are recorded in this table from years 2000 to 2007. You may note that the total for year 2007 is 7x higher than that of year 2000.

8. There is relatively higher incidence in males than females, among the elderly and in school children populations with large difference between sexes (as can be seen by the taller blue bars).There is relatively higher incidence in males than females, among the elderly and in school children populations with large difference between sexes (as can be seen by the taller blue bars).

9. Work ability index New Delhi, India In another study (WKC, 2009), the impact on heat on work ability can be considered as one chronic condition with a quantifiable link to climate change. We can make evaluation of the impact on work ability, assuming that working people reduce their work output per hour during hot hours in accordance with the international standard for work in heat (ISO, 1989). When the calculation uses the Wet Bulb Global Temperature (WBGT) outdoors in the sun, the losses in a heavy laboring job (500W) become extreme, and in fact during the middle of the day, no work of this type can be carried out. For a person working with less physical demands (200W) the work ability losses are less, but still almost 100% in the middle of the day in May in New Delhi, India.In another study (WKC, 2009), the impact on heat on work ability can be considered as one chronic condition with a quantifiable link to climate change. We can make evaluation of the impact on work ability, assuming that working people reduce their work output per hour during hot hours in accordance with the international standard for work in heat (ISO, 1989). When the calculation uses the Wet Bulb Global Temperature (WBGT) outdoors in the sun, the losses in a heavy laboring job (500W) become extreme, and in fact during the middle of the day, no work of this type can be carried out. For a person working with less physical demands (200W) the work ability losses are less, but still almost 100% in the middle of the day in May in New Delhi, India.

10. Climate variability and occurrence of diarrhea and cholera: Kolkata, India, 1999-2008 WKC is currently supporting research carried out by India�s National Institute for Cholera and Enteric Diseases (NICED) on the relationship between climate variables and diarrhoeal diseases, including cholera. Aside from the well-known periodicity of cholera outbreaks (above graph) the study is trying to ascertain whether the upward trend of cholera (below graph) is related to climate variables, such as ambient temperature and rainfall. WKC is currently supporting research carried out by India�s National Institute for Cholera and Enteric Diseases (NICED) on the relationship between climate variables and diarrhoeal diseases, including cholera. Aside from the well-known periodicity of cholera outbreaks (above graph) the study is trying to ascertain whether the upward trend of cholera (below graph) is related to climate variables, such as ambient temperature and rainfall.

11. Climate variability and occurrence of diarrhea and cholera: Kolkata, India, 1999-2008 One interesting aspect of this study is the relationship between ambient temperature and cholera outbreaks. The relationship between sea surface temperature and cholera outbreaks is well established. This pilot research is also taking into account these variables, specifically remote-sensing data on Sea Surface Temperature and Chlorophyll-A, which are known to influence Cholera outbreaks. It is important to ascertain the predictive value of easily available indicators, such as minimum or maximum ambient temperature, for the occurrence of cholera or diarrheal outbreaks. For instance, in this case, Tmax and Tmin seem to be equally correlated to occurrence of cholera, but that may not be the case in different geographical settings. Dr Nair of NICED surely will elaborate more on this research project that he leads as principal investigator. One interesting aspect of this study is the relationship between ambient temperature and cholera outbreaks. The relationship between sea surface temperature and cholera outbreaks is well established. This pilot research is also taking into account these variables, specifically remote-sensing data on Sea Surface Temperature and Chlorophyll-A, which are known to influence Cholera outbreaks. It is important to ascertain the predictive value of easily available indicators, such as minimum or maximum ambient temperature, for the occurrence of cholera or diarrheal outbreaks. For instance, in this case, Tmax and Tmin seem to be equally correlated to occurrence of cholera, but that may not be the case in different geographical settings. Dr Nair of NICED surely will elaborate more on this research project that he leads as principal investigator.

12. Effects of Climatic Factors on Diarrheal Diseases and Malaria: Jhapa District, Nepal, 1999-2008 In a recent study done by the Centre with the Nepal Health Research Council (NHRC) on Evaluation of the Effects of Climatic Factors on the Occurrence of Diarrheal Diseases and Malaria: A Pilot Retrospective Study in Jhapa District, Nepal, the findings are shown in the tables. Table 1 shows the correlation of climatic variables with malaria. Maximum and minimum temperature and rainfall have positive correlation with malaria though the strength of correlation is low. But the relative humidity at morning and evening have not shown positive correlations with malaria. Similarly, Table 2 shows the correlation of climatic variables with diarrhoea. Maximum and Minimum Temperature and rainfall have positive correlation with diarrhoea though the strength of correlation is low. But the relative humidity at morning and evening have not shown positive correlations with diarrhoea. In time series analysis done, none of the climatic variables are significant predictors for malaria and diarrhoea. Designed and implemented as a pilot research project to assess the impact of climate change in human health in one of the districts of Eastern Nepal, the short-duration data was considered as unable to give a clear scenario of association between change in climate and diseases of concern and a key recommendation was to do a prospective study. Dr Bhandari from NHRC will surely elaborate more on this research project that he led as principal investigator. Additional data: A study carried out by Department of Hydrology and Meteorology shows that the mean annual temperature of Nepal is in general in an increasing trend at 0.04 �C/year. The trend of malaria and maximum temperature do not show any increasing or decreasing trend of disease with increase or decrease in the maximum temperature. This can be explained by the fact that the change in temperature is very minimal and difficult to detect in 10 years period. The trend of minimum temperature is decreasing with minimal change whereas the trend of malaria shows increasing which can be explained by the fact that the days in the winter seasons are becoming warmer which may play a role positively in the breeding of mosquitoes.In a recent study done by the Centre with the Nepal Health Research Council (NHRC) on Evaluation of the Effects of Climatic Factors on the Occurrence of Diarrheal Diseases and Malaria: A Pilot Retrospective Study in Jhapa District, Nepal, the findings are shown in the tables. Table 1 shows the correlation of climatic variables with malaria. Maximum and minimum temperature and rainfall have positive correlation with malaria though the strength of correlation is low. But the relative humidity at morning and evening have not shown positive correlations with malaria. Similarly, Table 2 shows the correlation of climatic variables with diarrhoea. Maximum and Minimum Temperature and rainfall have positive correlation with diarrhoea though the strength of correlation is low. But the relative humidity at morning and evening have not shown positive correlations with diarrhoea. In time series analysis done, none of the climatic variables are significant predictors for malaria and diarrhoea. Designed and implemented as a pilot research project to assess the impact of climate change in human health in one of the districts of Eastern Nepal, the short-duration data was considered as unable to give a clear scenario of association between change in climate and diseases of concern and a key recommendation was to do a prospective study. Dr Bhandari from NHRC will surely elaborate more on this research project that he led as principal investigator. Additional data: A study carried out by Department of Hydrology and Meteorology shows that the mean annual temperature of Nepal is in general in an increasing trend at 0.04 �C/year. The trend of malaria and maximum temperature do not show any increasing or decreasing trend of disease with increase or decrease in the maximum temperature. This can be explained by the fact that the change in temperature is very minimal and difficult to detect in 10 years period. The trend of minimum temperature is decreasing with minimal change whereas the trend of malaria shows increasing which can be explained by the fact that the days in the winter seasons are becoming warmer which may play a role positively in the breeding of mosquitoes.

13. Role of epidemiology Identify�the health effects,�vulnerable populations and areas Assess needs and develop an action plan Monitor health co-benefits and/or damages Develop additional measures and policies There is no blueprint on how to start formulating policies and implementing relevant programmes but there is a need to clearly identify a number of items ensuring and demonstrating effective intersectoral action resulting to multiple benefits from identifying the risks posed by climate change, reducing the risks and the political commitment to sustain actions. Epidemiology plays a critical role in this by being able to show the causal link or correlations supplying the evidence that support evidence-based changes in policies, behaviours and advocacy.There is no blueprint on how to start formulating policies and implementing relevant programmes but there is a need to clearly identify a number of items ensuring and demonstrating effective intersectoral action resulting to multiple benefits from identifying the risks posed by climate change, reducing the risks and the political commitment to sustain actions. Epidemiology plays a critical role in this by being able to show the causal link or correlations supplying the evidence that support evidence-based changes in policies, behaviours and advocacy.

14. What should be done? Health sector The diverse, widespread, long-term and inequitable distribution of health risks attributable to climate change makes climate change a truly global challenge � calling for unprecedented degree of leadership, partnership and inter-sectoral actions. The Regional Conference is well appreciated in the spirit of bringing together epidemiology experts and people from different disciplines putting both adaptation and mitigation and its governance high in the SEA regional agenda cascading to national agenda and frontline local agenda. Although not entirely a new phenomenon, climate change and health is not a subject embedded in school curricula, thus knowledge management and education in general and capacity building of sectors including the health sector has to be done and strengthened. In the words of the WHO Director-General �Citizens, too, need to be fully informed of the health issues. In the end, it is their concern that can spur policy-makers to take the right actions, urgently.� In this respect, I would like to also highlight the �Training Course for Public Health Professionals on Protecting our Health from Climate Change� being piloted by WHO SEARO. In reducing the global carbon footprint of WHO, some examples of actions already taken have been: WHO/UNAIDS New Building was constructed with an ecological approach: resource efficiency and renewable energy; Large number of HQ official cars are hybrids : low petrol consumption and low CO2 emissions; The LSS / XEROX project has reduced by more than half the number of photocopiers, printers scanners and faxes. Electricity , cartridges and papers consumption has been also reduced; and In all the HQ toilets, corridors and underground parking, work is in progress to install motion sensors that turn the lights on only when human presence is detected. The Regional Initiative on Environment and Health in Southeast and East Asian Countries (�Our Environment is our Health�) began in 2004 with a high-level meeting followed by another high-level meeting in 2005 in Bangkok which resulted in a draft charter agreeing on work plans to address priority environmental health issues (2007-2010) � air quality; water supply, hygiene and sanitation; solid and hazardous waste; toxic chemicals and hazardous substances; climate change, ozone depletion and ecosystem changes; and contingency planning, preparedness and response in environmental health emergencies. The New Delhi Declaration on the impacts of climate change on human health signed on September 2008 was a declaration signed by the health ministers of WHO�s South-East Asia Region (SEAR), which urge all Member States as well as the WHO Director-General and the Regional Director of the SEAR to continue to provide leadership and technical support in building partnerships between governments, the UN and various global health initiatives and partnerships, academia, professional bodies, NGOs, the private sector, the media and civil society, to jointly advocate and effectively follow-up on all aspects of the Declaration on climate change and human health in the SEAR The diverse, widespread, long-term and inequitable distribution of health risks attributable to climate change makes climate change a truly global challenge � calling for unprecedented degree of leadership, partnership and inter-sectoral actions. The Regional Conference is well appreciated in the spirit of bringing together epidemiology experts and people from different disciplines putting both adaptation and mitigation and its governance high in the SEA regional agenda cascading to national agenda and frontline local agenda. Although not entirely a new phenomenon, climate change and health is not a subject embedded in school curricula, thus knowledge management and education in general and capacity building of sectors including the health sector has to be done and strengthened. In the words of the WHO Director-General �Citizens, too, need to be fully informed of the health issues. In the end, it is their concern that can spur policy-makers to take the right actions, urgently.� In this respect, I would like to also highlight the �Training Course for Public Health Professionals on Protecting our Health from Climate Change� being piloted by WHO SEARO. In reducing the global carbon footprint of WHO, some examples of actions already taken have been: WHO/UNAIDS New Building was constructed with an ecological approach: resource efficiency and renewable energy; Large number of HQ official cars are hybrids : low petrol consumption and low CO2 emissions; The LSS / XEROX project has reduced by more than half the number of photocopiers, printers scanners and faxes. Electricity , cartridges and papers consumption has been also reduced; and In all the HQ toilets, corridors and underground parking, work is in progress to install motion sensors that turn the lights on only when human presence is detected. The Regional Initiative on Environment and Health in Southeast and East Asian Countries (�Our Environment is our Health�) began in 2004 with a high-level meeting followed by another high-level meeting in 2005 in Bangkok which resulted in a draft charter agreeing on work plans to address priority environmental health issues (2007-2010) � air quality; water supply, hygiene and sanitation; solid and hazardous waste; toxic chemicals and hazardous substances; climate change, ozone depletion and ecosystem changes; and contingency planning, preparedness and response in environmental health emergencies. The New Delhi Declaration on the impacts of climate change on human health signed on September 2008 was a declaration signed by the health ministers of WHO�s South-East Asia Region (SEAR), which urge all Member States as well as the WHO Director-General and the Regional Director of the SEAR to continue to provide leadership and technical support in building partnerships between governments, the UN and various global health initiatives and partnerships, academia, professional bodies, NGOs, the private sector, the media and civil society, to jointly advocate and effectively follow-up on all aspects of the Declaration on climate change and human health in the SEAR

15. Intersectoral Actions Adapt and collaborate with other sectors Assess impact of interventions and co-benefits Mobilize champions