Global diarrhoea action plan needs integrated climate-based surveillance
Authors: Ali S Akanda, Antarpreet S Jutla, Rita R Colwell
Journal: The Lancet Global Health (2014)

Diarrhoeal diseases are the second most common cause of deaths of children, killing more than 1·5 million children annually and infecting billions more.1Wardlaw T Salama P Brocklehurst C et al.Diarrhoea: why children are still dying and what can be done.Lancet. 2010; 375: 870-872Summary Full Text Full Text PDF PubMed Scopus (159) Google Scholar, 2Santosham M Chandran A Fitzwater S et al.Progress and barriers for the control of diarrhoeal disease.Lancet. 2010; 376: 63-67Summary Full Text Full Text PDF PubMed Scopus (167) Google Scholar The recently released Global Action Plan for Pneumonia and Diarrhoea (GAPPD) is a comprehensive strategy document outlining plans to end preventable deaths from these two killer diseases by 2025.3WHO/UNICEF2013 Global action plan for pneumonia and diarrhoea, Geneva, CH.http://www.unicef.org/media/files/Final_GAPPD_main_Report-_EN-8_April_2013.pdfGoogle Scholar The document calls for a global integrated action plan, spearheaded by UNICEF and WHO, focused on coordination of several action strategies. Additional publications supplement the GAPPD document with information on various bottlenecks and barriers, and solutions to achieve the goals.4Chan M Lake A Integrated action for the prevention and control of pneumonia and diarrhea.Lancet. 2013; 381: 1436-1437Summary Full Text Full Text PDF PubMed Scopus (12) Google Scholar However, key questions remain about knowledge gained from existing intervention strategies and how they can be implemented globally. Treatment procedures such as oral rehydration solution (ORS), antibiotics, and intravenous fluids have saved lives during epidemics, and prevention measures such as access to vaccines, water, sanitation, and hygiene (WASH), and simple filtration solutions, have reduced infection transmission at local and small-regional scales.1Wardlaw T Salama P Brocklehurst C et al.Diarrhoea: why children are still dying and what can be done.Lancet. 2010; 375: 870-872Summary Full Text Full Text PDF PubMed Scopus (159) Google Scholar, 2Santosham M Chandran A Fitzwater S et al.Progress and barriers for the control of diarrhoeal disease.Lancet. 2010; 376: 63-67Summary Full Text Full Text PDF PubMed Scopus (167) Google Scholar, 5Colwell RR Huq A Islam MS et al.Reduction of cholera in Bangladeshi villages by simple filtration.Proc Nat Acad Sci USA. 2003; 100: 1051-1055Crossref PubMed Scopus (268) Google Scholar However, such interventions cannot easily be scaled up across vulnerable regions, and thus have not been able to control the increasing global burden of diarrhoeal diseases. In fact, data from UNICEF and WHO show that global focus on and necessary funding for ORS has plateaued since the 1990s;1Wardlaw T Salama P Brocklehurst C et al.Diarrhoea: why children are still dying and what can be done.Lancet. 2010; 375: 870-872Summary Full Text Full Text PDF PubMed Scopus (159) Google Scholar, 2Santosham M Chandran A Fitzwater S et al.Progress and barriers for the control of diarrhoeal disease.Lancet. 2010; 376: 63-67Summary Full Text Full Text PDF PubMed Scopus (167) Google Scholar only about 39% of children with diarrhoea in the developing world actually receive recommended treatment. Similarly, uptake of zinc and antibiotics has been poor, even after a decade of successful use in various epidemics.3WHO/UNICEF2013 Global action plan for pneumonia and diarrhoea, Geneva, CH.http://www.unicef.org/media/files/Final_GAPPD_main_Report-_EN-8_April_2013.pdfGoogle Scholar The challenge remains—how can we provide safe drinking water and sanitation facilities to more than 1 billion people? Perhaps this goal is possible with strong political and societal commitment, but, with the cost of implementation in present economic trends, many developing countries are likely to miss the Millennium Development Goals (MDGs) in 2015, and perhaps the GAPPD targets in 2025 (eg, India, with more than 1 billion people, has only about 35% sanitation coverage).3WHO/UNICEF2013 Global action plan for pneumonia and diarrhoea, Geneva, CH.http://www.unicef.org/media/files/Final_GAPPD_main_Report-_EN-8_April_2013.pdfGoogle Scholar Thus, innovative ways to deliver established treatment procedures and maximise WASH access by integration of engineering and public-health efforts are much needed.5Colwell RR Huq A Islam MS et al.Reduction of cholera in Bangladeshi villages by simple filtration.Proc Nat Acad Sci USA. 2003; 100: 1051-1055Crossref PubMed Scopus (268) Google Scholar The role of large-scale climate phenomena in provision of conditions conducive to the propagation and transmission of pathogens and disease is well accepted.6Colwell RR Global climate and infectious disease: the cholera paradigm.Science. 1996; 274: 2025-2031Crossref PubMed Scopus (969) Google Scholar Significant spatial and temporal variability occurs in diarrhoeal disease and mortality patterns across affected regions. Results of recent research have shown that pathogen growth, contamination and exposure, and the occurrence and severity of diarrhoeal outbreaks can be moderated by ambient environmental and climatic conditions.7Bandyopadhyay S Kanji S Wang L The impact of rainfall and temperature variation on diarrhoeal prevalence in sub-Saharan Africa.Appl Geogr. 2012; 33: 63-72Crossref Scopus (94) Google Scholar, 8Jutla AS Whitcombe E Hasan N et al.Environmental factors influencing epidemic cholera.Am J Trop Med Hyg. 2013; 89: 597-607Crossref PubMed Scopus (98) Google Scholar, 9Levy K Hubbard AE Eisenberg JNS Seasonality of rotavirus disease in the tropics: a systematic review and meta-analysis.Intl J Epidem. 2009; 38: 1487-1496Crossref PubMed Scopus (204) Google Scholar Large-scale climate events, such as droughts or floods, can directly affect available water quantity and quality, and, subsequently, access to WASH in large areas.8Jutla AS Whitcombe E Hasan N et al.Environmental factors influencing epidemic cholera.Am J Trop Med Hyg. 2013; 89: 597-607Crossref PubMed Scopus (98) Google Scholar, 10Akanda AS Jutla AS Gute DM Evans T Islam S Reinforcing cholera intervention through prediction aided prevention.Bull World Health Organ. 2012; 90: 243-244Crossref PubMed Scopus (18) Google Scholar A review of publications on global diarrhoeal burden, however, shows that the roles of climate or the ambient environment are yet to be recognised in plans or strategy documents.1Wardlaw T Salama P Brocklehurst C et al.Diarrhoea: why children are still dying and what can be done.Lancet. 2010; 375: 870-872Summary Full Text Full Text PDF PubMed Scopus (159) Google Scholar, 2Santosham M Chandran A Fitzwater S et al.Progress and barriers for the control of diarrhoeal disease.Lancet. 2010; 376: 63-67Summary Full Text Full Text PDF PubMed Scopus (167) Google Scholar As a result, a major global action plan such as the GAPPD does not draw attention to the potential of early warning systems based on climatic and environmental surveillance in strengthening of primary prevention strategies or intervention planning.3WHO/UNICEF2013 Global action plan for pneumonia and diarrhoea, Geneva, CH.http://www.unicef.org/media/files/Final_GAPPD_main_Report-_EN-8_April_2013.pdfGoogle Scholar, 4Chan M Lake A Integrated action for the prevention and control of pneumonia and diarrhea.Lancet. 2013; 381: 1436-1437Summary Full Text Full Text PDF PubMed Scopus (12) Google Scholar Climate-based early warning systems can provide reliable information on water quality and quantity, natural hazards, and population vulnerability to potential diarrhoeal disease outbreaks. Such predictive relationships could enable identification of especially vulnerable communities 2–3 months before epidemics occur, and allow timely intervention. For example, recent studies show that location and intensity of cholera outbreaks can be predicted up to 3 months in advance in the Bengal Delta region with understanding of underlying hydroclimatology and satellite-derived environmental variables.8Jutla AS Whitcombe E Hasan N et al.Environmental factors influencing epidemic cholera.Am J Trop Med Hyg. 2013; 89: 597-607Crossref PubMed Scopus (98) Google Scholar, 10Akanda AS Jutla AS Gute DM Evans T Islam S Reinforcing cholera intervention through prediction aided prevention.Bull World Health Organ. 2012; 90: 243-244Crossref PubMed Scopus (18) Google Scholar Similarly, for Haiti, Pakistan, and Mozambique, different sets of hydroclimatological factors can result in cholera outbreaks.7Bandyopadhyay S Kanji S Wang L The impact of rainfall and temperature variation on diarrhoeal prevalence in sub-Saharan Africa.Appl Geogr. 2012; 33: 63-72Crossref Scopus (94) Google Scholar, 8Jutla AS Whitcombe E Hasan N et al.Environmental factors influencing epidemic cholera.Am J Trop Med Hyg. 2013; 89: 597-607Crossref PubMed Scopus (98) Google Scholar Vaccines for rotavirus and cholera—the two diseases with the highest child mortality rates and a significant fraction of the global diarrhoeal burden—are at preliminary stages of implementation.3WHO/UNICEF2013 Global action plan for pneumonia and diarrhoea, Geneva, CH.http://www.unicef.org/media/files/Final_GAPPD_main_Report-_EN-8_April_2013.pdfGoogle Scholar The use of vaccination as a global primary-prevention strategy can also be rapidly strengthened with the help of an early-warning system, by planning of targeted delivery in vulnerable populations. A systematic synthesis of hydroclimatic understanding with microbiological and epidemiological evidence of pathogen transmission pathways will also create a necessary platform for identification of effects of global climatic and environmental changes on disease dynamics. In addition to investment in medicinal development, ORS distribution, and WASH infrastructure, there is tremendous potential in the use of the vast and freely available climate and satellite remote sensing datasets and space and time information on the dominant underlying processes behind diarrhoeal disease outbreaks. Without the inclusion of such information, we cannot accurately assess population vulnerability or the public-health response capacity of affected regions, nor can we harness the potential of early-warning systems. Climatic and environmental surveillance systems can successfully monitor affected and vulnerable regions over large swathes of territory and identify hotspot areas with useful lead time to intervene.6Colwell RR Global climate and infectious disease: the cholera paradigm.Science. 1996; 274: 2025-2031Crossref PubMed Scopus (969) Google Scholar, 10Akanda AS Jutla AS Gute DM Evans T Islam S Reinforcing cholera intervention through prediction aided prevention.Bull World Health Organ. 2012; 90: 243-244Crossref PubMed Scopus (18) Google Scholar To control the global diarrhoeal disease burden will need a focus on a combination of recent advances in global predictive and surveillance capabilities using climatic and environmental information, and proven successes in treatment and prevention. Coupled with advances at the local scale of diarrhoeal treatment, innovative solutions such as simple filtration measures during extreme weather conditions, and vaccines as proven by improved survival rates, an integrated climate-based surveillance mechanism could provide predictive monitoring of vulnerable regions and strengthen the global health community's ability to reduce the disease burden. We declare that we have no conflicts of interest.