What email address or phone number would you like to use to sign in to Docs.com?
If you already have an account that you use with Office or other Microsoft services, enter it here.
Or sign in with:
Signing in allows you to download and like content, and it provides the authors analytical data about your interactions with their content.
Embed code for: Sickle Cell Anaemia in a Changing World
Select a size
Perspective Sickle Cell Anaemia in a Changing World Edward Fottrell1,2, David Osrin1* 1Institute for Global Health, UCL Institute of Child Health, London, United Kingdom, 2Umea ˚ Centre for Global Health Research, Umea ˚ University, Umea ˚, Sweden Populations and their health are dy- namic. Societal, environmental, and eco- nomic changes lead to changes in rates of birth, death, and disease, often described as transitions in mortality, demography, and epidemiology. The notion of epide- miologic transition provides an insight into the relationship between levels of overall mortality and the distribution of its causes [1–3], in which the greatest changes arise from the survival of children and young women. Recent falls in global child mortality are good news , but will lead to increases in the relative burdens of morbidity and disability in children who would previously have died, and of congenital malformations and inherited disorders. The work of Fre´de´ric Piel and colleagues on sickle cell anaemia (SCA), published in this week’s PLOS Medicine , speaks strongly to this point: SCA is an inherited disease whose global importance will increase in terms of absolute numbers and relative population burden. SCA occurs when individuals are homozygous for sickle haemoglobin (HbS) in place of normal adult haemoglobin, and is the most common form of sickle cell disorder (SCD) . Piel and colleagues have collated HbS allele frequency surveys and used them in models to generate a global distribution map and estimate the numbers of infants born heterozygotic and homozygotic for HbS. Using population and mortality projections, they predict an increase in the numbers of newborns with SCA to over 400,000 in 2050. They also estimate the potential mortality effects of four care-provision scenarios, with a best- case scenario that between 7.5 and 15.5 million newborn lives could be saved, most of them in Africa. Modelled estimates are a growth area in global health. Whilst useful at supra- national and national levels, their emer- gence highlights the lack of reliable data on populations, disease, and mortality across most of the world: precisely the sort of information that policy makers and health planners need. The utility of estimates for planning screening pro- grammes, infrastructural and human re- source requirements, and clinical care protocols at sub-national levels is likely to be limited where the generalisability of assumptions is challenged by diversity at the local level. Even at a global level, estimates can cause confusion. Research teams using different models may, for example, come to different conclusions . Piel et al. have combined available data, statistical methods, and assumptions to predict current burdens and future trends. Their uncertainties are described clearly, and a preoccupation with meth- odological critiques can easily distract us from the public health concerns that estimates raise. The epidemiologic transition has been reframed as a health transition that involves sociocultural, behavioural, and health service factors , and policy and health services must respond to changing disease burdens. Unfortunately, the notion of transitions is general. Parallel transitions are happening in different groups within one nation, the best example being differences between socioeconomic groups. Rates of transition vary with local environment, and counter-transition is even possible . Policy makers must set priorities in an environment of multiple burdens, unfinished agendas, competing discourses, and the voices of interest groups , a process that has been described as a chaos of purposes and accidents . In an environment of Realpolitik, the generation of estimates of burden is important for advocacy. Char- acteristically, investigators working in an important public health field that has not received global attention lay down the strategic epidemiology [7,12], as Piel and colleagues are doing, demonstrating that lack of progress will hinder efforts to attain targets such as those of the Millennium Development Goals. Quantifying the problem is important, but not sufficient. In a consideration of issue attention for newborn health, Jeremy Shiffman considered four elements: the power of the actors involved, new ideas that can be brought to the table, the characteristics of the issue in terms of attractiveness and tractability, and politi- cal context . The kind of strategic epidemiology that the SCA figures exem- plify needs to be linked with granular understanding of local epidemiology and service provision . SCA poses a partic- ular challenge in terms of tractability. Haematopoietic stem cell transplantation, Citation: Fottrell E, Osrin D (2013) Sickle Cell Anaemia in a Changing World. PLoS Med 10(7): e1001483. doi:10.1371/journal.pmed.1001483 Published July 16, 2013 Copyright: 2013 Fottrell, Osrin. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: EF is supported at Umea ˚ Centre for Global Health Research by FAS, the Swedish Council for Working Life and Social Research. DO is supported by a Wellcome Trust Senior Research Fellowship in Clinical Science (091561). The funders played no role in the preparation of the manuscript. Competing Interests: The authors have no competing interests to declare. Abbreviations: HbS, sickle haemoglobin; SCA, sickle cell anaemia; SCD, sickle cell disorder * E-mail: firstname.lastname@example.org Provenance: Commissioned; not externally peer reviewed. Linked Research Article This Perspective discusses the fol- lowing new study published in PLOS Medicine: Piel FB, Hay SI, Gupta S, Weatherall DJ, Williams TN (2013) Global Bur- den of Sickle Cell Anaemia in Children under Five, 2010–2050: Modelling Based on Demographics, Excess Mortality, and Interventions. PLoS Med 10(7): e1001484. doi:10. 1371/journal.pmed.1001484 PLOS Medicine | www.plosmedicine.org 1 July 2013 | Volume 10 | Issue 7 | e1001483 an emerging cure, is currently too costly a technology for the countries on which the burden predominantly falls, as is hydroxy- urea therapy for children at high risk of illness. Survival, health, and well-being can all be improved substantially, but rely on health care systems with a certain level of functionality. Piel and colleagues sug- gest that the priority is to identify births of infants with SCA, but that such births could be avoided through genetic coun- selling and prenatal diagnosis. Termina- tion of pregnancy is one of several options, which include preconception genetic screening and strategic reproductive choic- es, education for carrier parents, and holistic management from infancy. Quite apart from the logistic and financial challenges, these approaches raise substan- tial ethical questions summarised in recent work from Ghana . Several interventions would be enor- mously helpful. Routine newborn screen- ing remains costly—but is likely to become less so—and may miss infants born at home. Penicillin prophylaxis and pneumo- coccal immunisation are possible in most health care systems. The most beneficial approach involves comprehensive care : family education, routine immunisa- tion, malaria prevention, nutrition and hydration, prophylactic antibiotics, folic acid supplements, transfusion when re- quired, support groups for children and their families, protocols for the manage- ment of acute events by health workers and—most importantly—regular follow- up. Human resources for health need to be well trained, and the medicines re- quired need to be affordable and available, including the pain relief required by many people with SCD . Steps towards a systematic approach are being taken . A 2006 World Health Assembly resolution on SCA recommends increased awareness in the international community and emphasises collaboration between countries, including technical support, development of practice models, and coordination . The World Health Organization has published a strategy for the African Region, with targets that include development and implementation of national control programmes in mem- ber states with high SCD prevalence, adoption of comprehensive health care management, and establishment of sur- veillance systems . The estimates from Piel and colleagues underscore the need for both collaborative responses and better data for planning and monitoring. Author Contributions Wrote the first draft of the manuscript: EF DO. Contributed to the writing of the manuscript: EF DO. ICMJE criteria for authorship read and met: EF DO. References 1. Omran AR (1971) The epidemiologic transition: a theory of the epidemiology of population change. Milbank Mem Fund Q 49: 509–538. 2. Omran AR (1983) The epidemiologic transition theory. A preliminary update. J Trop Pediatr 29: 305–316. 3. Salomon JA, Murray CJL (2002) The epidemio- logic transition revisited: compositional models for causes of death by age and sex. Popul Dev Rev 28: 205–228. 4. World Health Organization (2013) World health statistics 2013. Geneva: World Health Organiza- tion. 5. Piel FB, Hay SI, Gupta S, Weatherall DJ, Williams TN (2013) Global Burden of Sickle Cell Anaemia in Children under Five, 2010–2050: Modelling Based on Demographics, Excess Mor- tality, and Interventions. PLoS Med 10: e1001484. doi:10.1371/journal.pmed.1001484 6. Piel FB, Patil AP, Howes RE, Nyangiri OA, Gething PW, et al. (2013) Global epidemiology of sickle haemoglobin in neonates: a contemporary geostatistical model-based map and population estimates. Lancet 381: 142–151. 7. Darlison MW, Modell B (2013) Sickle-cell disorders: limits of descriptive epidemiology. Lancet 381: 98–99. 8. Caldwell JC (1993) Health transition: the cultural, social and behavioural determinants of health in the third world. Soc Sci Med 36: 125–135. 9. Frenk J, Bobadilla JL, Sepulveda J, Lopez Cervantes M (1989) Health transition in middle- income countries: new challenges for health care. Health Policy Plan 4: 29–39. 10. Keeley J, Scoones I (1999) Understanding environmental policy processes: a review. Brighton (UK): Institute of Development Studies. Working Paper 89. 120 p. 11. Clay E, Schaffer B, editors (1986) Room for manoeuvre: an explanation of public policy in agriculture and rural development. London: Heinemann. 12. Smith KR, Corvala´n C, Kjellstro¨m T (1999) How much global ill health is attributable to environ- mental factors? Epidemiology 10: 573–584. 13. Shiffman J (2010) Issue attention in global health: the case of newborn survival. Lancet 375: 2045–2049. 14. Edwin AK, Edwin F, Etwire V (2011) Controlling sickle cell disease in Ghana—ethics and options. Pan African Med J 10: 14–22. 15. McCavit TL (2012) Sickle cell disease. Pediatr Rev 33: 195–206. 16. Anderson M, Adnani M (2013) ‘‘You just have to live with it’’: coping with sickle cell disease in Jamaica. Qual Health Res 23: 655–664. 17. Aygun B, Odame I (2012) A global perspective on sickle cell disease. Pediatr Blood Cancer 59: 386– 390. 18. Fifty-ninth World Health Assembly (2006) Reso- lutions: WHA59.20—sickle cell anaemia. Gene- va: World Health Organization. Available: http://apps.who.int/gb/ebwha/pdf_files/ WHA59-REC1/e/Resolutions-en.pdf. Accessed 12 June 2013. 19. World Health Organization (2010) Sickle-cell disease: a strategy for the WHO African Region. AFR/RC60/8. Malabo: World Health Organi- zation Regional Office for Africa. PLOS Medicine | www.plosmedicine.org 2 July 2013 | Volume 10 | Issue 7 | e1001483 f acute events by health workers and—most importantly—regular follow- up. Human resources for health need to be well trained, and the medicines re- quired need to be affordable and available, including the pain relief required by many people with SCD . Steps towards a systematic approach are being taken . A 2006 World Health Assembly resolution on SCA recommends increased awareness in the international community and emphasises collaboration between countries, including technical support, development of practice models, and coordination . The World Health Organization has published a str