Old and new challenges related to global burden of diarrhoea
Authors: Karen H Keddy
Journal: The Lancet Infectious Diseases (2018)

The Global Burden of Disease (GBD) project has five major objectives: improve control of disease burdens, generate opportunities for informed debate, identify disease control priorities, create knowledge about diseases, and enable rational allocation of resources for disease control.1Lopez AD Mathers C Ezzati M Jamison DT Murray CJ Measuring the global burden of disease and risk factors, 1990–2001.in: Lopez AD Mathers C Ezzati M Jamison DT Murray CJ Global Burden of Disease and Risk Factors. Oxford University Press, New York2006: 1-13Crossref Google Scholar Of the diseases that any national Ministry of Health should combat, diarrhoeal diseases are among the most challenging. Diarrhoeal diseases are not diseases of excess, habit, or heredity, and optimal interventions, with few exceptions, might fall outside the ministerial scope. Food and water are major vehicles of diarrhoeal disease and remain unavoidable risk factors for morbidity and mortality. By refining their methods, Robert Reiner and colleagues2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar have updated estimates of global diarrhoea burden for 2016,2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar highlighting current and new causes for concern, reiterating the excessive morbidity and mortality in children younger than 5 years, defining the association between case-fatality ratio and Socio-demographic Index (SDI), and emphasising the vulnerability of the ageing global population. Diarrhoeal diseases affect all ages, but particularly the young and the elderly.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Despite a 57% reduction in diarrhoea deaths since 2000, children younger than 5 years remain the most vulnerable group to diarrhoeal2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar and foodborne diseases.3Kirk MD Pires SM Black RE et al.World Health Organization estimates of the global and regional disease burden of 22 foodborne bacterial, protozoal, and viral diseases, 2010: a data synthesis.PLoS Med. 2015; 12: e1001921Crossref PubMed Scopus (777) Google Scholar An estimated 1·1 billion total episodes of diarrhoea, about 1·8 episodes per child, occurred in this age group in 2016 compared with an incidence of 0·90 episodes (95% uncertainty interval [UI] 0·82–1·00) per person-year in adults older than 70 years.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Although the rotavirus vaccine has undoubtedly affected the burden of diarrhoeal disease in children, rotavirus diarrhoea remains the commonest cause of death in children younger than 5 years due to diarrhoea (20·3 deaths [95% UI 16·6–24·5] per 100 000),2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar suggesting that the vaccine is still underused globally. Ageing populations have created further challenges for the control of diarrhoeal disease. The UN reported that the population of individuals older than 60 years will increase globally from 962·3 million in 2017 to 2080·5 million in 2050, primarily in Africa, where a projected 230% increase will occur.4United NationsDepartment of Economic and Social AffairsPopulation DivisionWorld Population Ageing 2017. United Nations, New York2017http://www.un.org/en/development/desa/population/publications/pdf/ageing/WPA2017_Report.pdfDate accessed: June 20, 2018Crossref Google Scholar In 2016, diarrhoea mortality was about three times greater in adults older than 70 years than in children younger than 5 years: the commonest cause of diarrhoea in elderly people was shigella, causing 18·4 deaths (95% UI 10·5–31·8) per 100 000.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Excessive mortality due to invasive shigellosis in adult women with HIV caring for sick children5Keddy KH Sooka A Crowther-Gibson P et al.Systemic shigellosis in South Africa.Clin Infect Dis. 2012; 54: 1448-1454Crossref PubMed Scopus (32) Google Scholar suggests interventions aimed at controlling childhood diarrhoea6Tickell KD Brander RL Atlas HE Pernica JM Walson JL Pavlinac PB Identification and management of Shigella infection in children with diarrhoea: a systematic review and meta-analysis.Lancet Glob Health. 2017; 5: e1235-e1248Summary Full Text Full Text PDF PubMed Scopus (40) Google Scholar might benefit vulnerable adults. In countries where case-fatality rates should be lower because of high SDI, HIV probably remains an important factor in disease outcome.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Cholera, which is associated with breakdowns in delivery of safe water, contributed to 1·5 deaths (95% UI 0·9–2·4) per 100 000 worldwide and was the third commonest cause of diarrhoeal death2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar occurring predominantly in countries with political and economic instability. Mapping the history of cholera outbreaks traces a narrative of conflict.7WHOCholera, 2016.Wkly Epidemiol Rec. 2017; 92: 521-530PubMed Google Scholar, 8Weill FX Domman D Njamkepo E et al.Genomic history of the seventh pandemic of cholera in Africa.Science. 2017; 358: 785-789Crossref PubMed Scopus (147) Google Scholar Clostridium difficile is often poorly investigated in countries with a low SDI,9Keeley AJ Beeching NJ Stott KE Roberts P Watson AJ Beadsworth MB Clostridium difficile: a healthcare-associated infection of unknown significance in adults in sub-Saharan Africa.Malawi Med J. 2016; 28: 66-69Crossref PubMed Scopus (12) Google Scholar and although it contributed little to global diarrhoeal mortality, it had the greatest impact on diarrhoeal mortality in high SDI countries (7761 total deaths).2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Climate change might directly and indirectly affect burden estimates in the future. The authors showed that SDI was associated with diarrhoea mortality, irrespective of age.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Climate change disproportionately threatens food production, and hence food security, in countries with a low SDI,10Watts N Amann M Ayeb-Karlsson S et al.The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health.Lancet. 2018; 391: 581-630Summary Full Text Full Text PDF PubMed Scopus (584) Google Scholar, 11Zinsstag J Crump L Schelling E et al.Climate change and One Health.FEMS Microbiol Lett. 2018; (published online June 1.)DOI:10.1093/femsle/fny085Crossref PubMed Scopus (56) Google Scholar with complications of food scarcity potentially overwhelming those countries where low SDI is associated with high case-fatality rates in children.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Malnutrition and stunting, which are associated with climate change,10Watts N Amann M Ayeb-Karlsson S et al.The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health.Lancet. 2018; 391: 581-630Summary Full Text Full Text PDF PubMed Scopus (584) Google Scholar, 11Zinsstag J Crump L Schelling E et al.Climate change and One Health.FEMS Microbiol Lett. 2018; (published online June 1.)DOI:10.1093/femsle/fny085Crossref PubMed Scopus (56) Google Scholar are risk factors for severe diarrhoea,12Troeger C Colombara DV Rao PC et al.Global disability-adjusted life-year estimates of long-term health burden and undernutrition attributable to diarrhoeal diseases in children younger than 5 years.Lancet Glob Health. 2018; 6: e255-e269Summary Full Text Full Text PDF PubMed Scopus (86) Google Scholar, 13Guerrant RL DeBoer MD Moore SR Scharf RJ Lima AA The impoverished gut—a triple burden of diarrhoea, stunting and chronic disease.Nat Rev Gastroenterol Hepatol. 2013; 10: 220-229Crossref PubMed Scopus (362) Google Scholar and flood and drought resulting from climate change10Watts N Amann M Ayeb-Karlsson S et al.The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health.Lancet. 2018; 391: 581-630Summary Full Text Full Text PDF PubMed Scopus (584) Google Scholar, 11Zinsstag J Crump L Schelling E et al.Climate change and One Health.FEMS Microbiol Lett. 2018; (published online June 1.)DOI:10.1093/femsle/fny085Crossref PubMed Scopus (56) Google Scholar have been further associated with increased burdens of diarrhoeal disease in affected areas.14Ghazani M FitzGerald G Hu W Toloo GS Xu Z Temperature variability and gastrointestinal infections: a review of impacts and future perspectives.Int J Environ Res Public Health. 2018; (published online April 16.)DOI:10.3390/ijerph15040766Crossref PubMed Scopus (22) Google Scholar Debate regarding disease control has affected strategies related to safe food, sanitation, and water, and socioeconomic and political stability. Implementation of these strategies has been inadequate, sometimes non-existent, and improvements remain vulnerable to regression. Insufficient resources in countries that have the greatest burden of diarrhoeal diseases have been detrimental to progress in global control of such diseases. This underfunding has caused unequal reductions in diarrhoeal disease burdens among countries.2GBD 2016 Diarrhoeal Disease CollaboratorsEstimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016.Lancet Infect Dis. 2018; (published online Sept 19.)http://dx.doi.org/10.1016/S1473-3099(18)30362-1Google Scholar Knowledge about and insight into diarrhoeal diseases have advanced, but improved granularity would enhance country-level management for all age groups. More high-quality data are needed on the complex cause-and-effect associations between stunting and diarrhoea, climate change, the role of comorbidities, acute versus subacute disease, and bloody versus non-bloody diarrhoea. By updating these GBD estimates, Reiner and colleagues have reminded us that substantial progress is needed to reduce the global burden of diarrhoea. We declare no competing interests. Estimates of the global, regional, and national morbidity, mortality, and aetiologies of diarrhoea in 195 countries: a systematic analysis for the Global Burden of Disease Study 2016Substantial progress has been made globally in reducing the burden of diarrhoeal diseases, driven by decreases in several primary risk factors. However, this reduction has not been equal across locations, and burden among adults older than 70 years requires attention. Full-Text PDF Open Access