Health-care worker mortality and the legacy of the Ebola epidemic
Authors: David K Evans, Markus Goldstein, Anna Popova
Journal: The Lancet Global Health (2015)

The recent outbreak of Ebola in West Africa will leave a legacy significantly deeper than the morbidity and mortality caused directly by the disease. Ebola deaths have been disproportionately concentrated among health personnel. By May, 2015, 0·02% of Guinea's population had died due to Ebola, compared with 1·45% of the country's doctors, nurses, and midwives. In Liberia and Sierra Leone, the differences are more dramatic, with 0·11% and 0·06% of the general population killed by Ebola versus 8·07% of the health-care workers in Liberia, and 6·85% in Sierra Leone.1WHOHealth worker Ebola infections in Guinea, Liberia and Sierra Leone: a preliminary report. World Health Organization, Geneva2015http://www.who.int/csr/resources/publications/ebola/health-worker-infections/en/Google Scholar, 2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar, 3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar, 4WHOEbola situation report, 20 May 2015. World Health Organization, Geneva2015http://apps.who.int/ebola/en/current-situation/ebola-situation-report-20-may-2015Google Scholar The fact that health-care workers are at greater risk of contracting Ebola will exacerbate existing skill shortages in countries that had few health personnel to begin with.We modelled how the loss of health-care workers—defined here as doctors, nurses, and midwives—to Ebola might affect maternal, infant, and under-5 mortality in Guinea, Liberia, and Sierra Leone, with the aim of characterising the order of magnitude of likely effects, not providing specific predictions. We combined data on: (1) health-care worker deaths from Ebola;1WHOHealth worker Ebola infections in Guinea, Liberia and Sierra Leone: a preliminary report. World Health Organization, Geneva2015http://www.who.int/csr/resources/publications/ebola/health-worker-infections/en/Google Scholar (2) the stock of health-care workers pre-Ebola;5WHOHealth workforce density per 1000 population.http://apps.who.int/gho/data/node.main.A1444Google Scholar (3) maternal, infant, and under-5 mortality rates for each country, pre-Ebola;2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar and (4) coefficients of health-care worker mortality, which capture the relation between health-care workers in a given country and different mortality rates (ie, maternal, infant, and under-5 mortality).3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle ScholarFor each of the three countries, we first calculated how many doctors, nurses, and midwives combined have died due to Ebola per 1000 of the population. We multiplied each pre-Ebola mortality rate (maternal, infant, and under-5) by 1 minus this fraction, multiplied by the health-care worker mortality coefficient. We then translated this figure into the percentage change in mortality relative to pre-Ebola rates (appendix).We constructed bounds based on the 95% CIs of the estimated coefficients of health-care worker mortality. These incorporate the estimation uncertainty associated with the health-care worker mortality coefficients and the pre-Ebola mortality rates, under the assumption that the latter uncertainty is constant across countries and over the period between the estimation of the health-care worker mortality coefficients (2006) and the present (2015). However, we were unable to account for the uncertainty surrounding the measurement of health-care worker mortality owing to a lack of data.As of late May, 2015, Guinea, Liberia, and Sierra Leone, respectively, had lost 78, 83, and 79 doctors, nurses, and midwives to Ebola. The largest effects of these health-care worker deaths for all three countries were on maternal mortality (table), namely increases of 38% (95% CI 26–50) in Guinea, 74% (51–97) in Sierra Leone, and as large as 111% (76–145) in Liberia, relative to pre-Ebola rates. Estimated effects on infant and under-5 mortality ranged from an increase of 7–20% and 10–28% across countries, respectively. However, in both of the latter cases the health-care worker mortality coefficients used were not statistically significant in the original study3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar and the range between the upper and lower bounds of the 95% CIs includes a zero effect (table).TableEffects of health-care worker deaths from Ebola on maternal, infant, and child mortalityDoctors, nurses, and midwivesMaternal mortality ratio (per 100 000 livebirths)Infant mortality rate (per 1000 livebirths)Under-5 mortality rate (per 1000 livebirths)Stock pre-EbolaStock post-Ebola% changePre-Ebola (2013)May 2015% change (95% CI)Pre-Ebola (2013)May 2015% change (95% CI)Pre-Ebola (2013)May 2015% change (95% CI)Guinea53955317−1%65089738% (26 to 50)65697% (−2 to 15)10111010% (−2 to 21)Liberia1029946−8%6401347111% (76 to 145)546420% (−4 to 43)719128% (−5 to 61)Sierra Leone11531074−7%1100191674% (51 to 97)10712113% (−3 to 29)16119119% (−4 to 41)Data are from author calculations based on Ebola mortality data from WHO,1WHOHealth worker Ebola infections in Guinea, Liberia and Sierra Leone: a preliminary report. World Health Organization, Geneva2015http://www.who.int/csr/resources/publications/ebola/health-worker-infections/en/Google Scholar population and maternal mortality data from World Development Indicators,2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar and health worker-mortality coefficients from Speybroeck et al.3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar Data on pre-Ebola stock of health workers is for the most recent years available for each country: 2004 (nurses and midwives) and 2005 (doctors) for Guinea, 2008 for Liberia, and 2010 for Sierra Leone. Open table in a new tab Combining these estimates with the most recent population numbers and rate of livebirths in each country pre-Ebola2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar suggests that an additional 4022 women would die per year in childbirth as a result of doctors, nurses, and midwives lost to Ebola. This would bring the countries back to rates of maternal mortality last seen in 2000 in Guinea and Sierra Leone, and 1995 in Liberia.2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google ScholarThese mortality estimates have limitations. The model's use of cross-country mortality coefficients assumes that the effect of health-care worker supply on maternal, infant, and under-5 mortality in Guinea, Liberia, and Sierra Leone is similar to the cross-country average and has not changed since those coefficients were estimated. This work further assumes that unmeasured elements of health systems (such an overall measure of quality), associated with both health-care worker density and mortality, are not driving the result. Data limitations make it difficult to account for these unmeasured factors, but one may consider that health-care workers are a crucial element of all other parts of an effectively functioning health-care system. However, these numbers demonstrate the potentially sizeable legacy that Ebola will leave.Ebola has weakened already fragile systems, and it should be the catalyst to strengthen the systems far beyond their pre-Ebola levels. Indeed, to reach the minimum 80% health coverage targeted by the Millennium Development Goals, 43 565 doctors, nurses, and midwives would need to be hired across the three countries. Our estimates suggest that substantial investment in health systems—and specifically in the health workforce—is urgently required not only to improve future epidemic preparedness and meet basic needs, but also to limit the secondary health effects of the current epidemic owing to the depletion of the health workforce.An extended version of this Correspondence can be found at http://documents.worldbank.org/curated/en/24652897. We declare no competing interests. No external funding was received for this work. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the World Bank and its affiliated organisations, nor those of the Executive Directors of the World Bank or the governments they represent. We thank Trina Haque, Patricio Marquez, and Shiyong Wang for their help in securing the data without which this work would not have been possible, as well as Kathleen Beegle, Timothy Bulman, Francisco Ferreira, and two anonymous reviewers for their suggestions. The recent outbreak of Ebola in West Africa will leave a legacy significantly deeper than the morbidity and mortality caused directly by the disease. Ebola deaths have been disproportionately concentrated among health personnel. By May, 2015, 0·02% of Guinea's population had died due to Ebola, compared with 1·45% of the country's doctors, nurses, and midwives. In Liberia and Sierra Leone, the differences are more dramatic, with 0·11% and 0·06% of the general population killed by Ebola versus 8·07% of the health-care workers in Liberia, and 6·85% in Sierra Leone.1WHOHealth worker Ebola infections in Guinea, Liberia and Sierra Leone: a preliminary report. World Health Organization, Geneva2015http://www.who.int/csr/resources/publications/ebola/health-worker-infections/en/Google Scholar, 2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar, 3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar, 4WHOEbola situation report, 20 May 2015. World Health Organization, Geneva2015http://apps.who.int/ebola/en/current-situation/ebola-situation-report-20-may-2015Google Scholar The fact that health-care workers are at greater risk of contracting Ebola will exacerbate existing skill shortages in countries that had few health personnel to begin with. We modelled how the loss of health-care workers—defined here as doctors, nurses, and midwives—to Ebola might affect maternal, infant, and under-5 mortality in Guinea, Liberia, and Sierra Leone, with the aim of characterising the order of magnitude of likely effects, not providing specific predictions. We combined data on: (1) health-care worker deaths from Ebola;1WHOHealth worker Ebola infections in Guinea, Liberia and Sierra Leone: a preliminary report. World Health Organization, Geneva2015http://www.who.int/csr/resources/publications/ebola/health-worker-infections/en/Google Scholar (2) the stock of health-care workers pre-Ebola;5WHOHealth workforce density per 1000 population.http://apps.who.int/gho/data/node.main.A1444Google Scholar (3) maternal, infant, and under-5 mortality rates for each country, pre-Ebola;2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar and (4) coefficients of health-care worker mortality, which capture the relation between health-care workers in a given country and different mortality rates (ie, maternal, infant, and under-5 mortality).3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar For each of the three countries, we first calculated how many doctors, nurses, and midwives combined have died due to Ebola per 1000 of the population. We multiplied each pre-Ebola mortality rate (maternal, infant, and under-5) by 1 minus this fraction, multiplied by the health-care worker mortality coefficient. We then translated this figure into the percentage change in mortality relative to pre-Ebola rates (appendix). We constructed bounds based on the 95% CIs of the estimated coefficients of health-care worker mortality. These incorporate the estimation uncertainty associated with the health-care worker mortality coefficients and the pre-Ebola mortality rates, under the assumption that the latter uncertainty is constant across countries and over the period between the estimation of the health-care worker mortality coefficients (2006) and the present (2015). However, we were unable to account for the uncertainty surrounding the measurement of health-care worker mortality owing to a lack of data. As of late May, 2015, Guinea, Liberia, and Sierra Leone, respectively, had lost 78, 83, and 79 doctors, nurses, and midwives to Ebola. The largest effects of these health-care worker deaths for all three countries were on maternal mortality (table), namely increases of 38% (95% CI 26–50) in Guinea, 74% (51–97) in Sierra Leone, and as large as 111% (76–145) in Liberia, relative to pre-Ebola rates. Estimated effects on infant and under-5 mortality ranged from an increase of 7–20% and 10–28% across countries, respectively. However, in both of the latter cases the health-care worker mortality coefficients used were not statistically significant in the original study3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar and the range between the upper and lower bounds of the 95% CIs includes a zero effect (table). Data are from author calculations based on Ebola mortality data from WHO,1WHOHealth worker Ebola infections in Guinea, Liberia and Sierra Leone: a preliminary report. World Health Organization, Geneva2015http://www.who.int/csr/resources/publications/ebola/health-worker-infections/en/Google Scholar population and maternal mortality data from World Development Indicators,2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar and health worker-mortality coefficients from Speybroeck et al.3Speybroeck N Kinfu Y Poz MD Evans D Reassessing the relationship between human resources for health, intervention coverage and health outcomes. World Health Organization, Geneva2006http://www.who.int/hrh/documents/reassessing_relationship.pdfGoogle Scholar Data on pre-Ebola stock of health workers is for the most recent years available for each country: 2004 (nurses and midwives) and 2005 (doctors) for Guinea, 2008 for Liberia, and 2010 for Sierra Leone. Combining these estimates with the most recent population numbers and rate of livebirths in each country pre-Ebola2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar suggests that an additional 4022 women would die per year in childbirth as a result of doctors, nurses, and midwives lost to Ebola. This would bring the countries back to rates of maternal mortality last seen in 2000 in Guinea and Sierra Leone, and 1995 in Liberia.2World BankWorld development indicators.http://data.worldbank.org/data-catalog/world-development-indicatorsDate: 2015Google Scholar These mortality estimates have limitations. The model's use of cross-country mortality coefficients assumes that the effect of health-care worker supply on maternal, infant, and under-5 mortality in Guinea, Liberia, and Sierra Leone is similar to the cross-country average and has not changed since those coefficients were estimated. This work further assumes that unmeasured elements of health systems (such an overall measure of quality), associated with both health-care worker density and mortality, are not driving the result. Data limitations make it difficult to account for these unmeasured factors, but one may consider that health-care workers are a crucial element of all other parts of an effectively functioning health-care system. However, these numbers demonstrate the potentially sizeable legacy that Ebola will leave. Ebola has weakened already fragile systems, and it should be the catalyst to strengthen the systems far beyond their pre-Ebola levels. Indeed, to reach the minimum 80% health coverage targeted by the Millennium Development Goals, 43 565 doctors, nurses, and midwives would need to be hired across the three countries. Our estimates suggest that substantial investment in health systems—and specifically in the health workforce—is urgently required not only to improve future epidemic preparedness and meet basic needs, but also to limit the secondary health effects of the current epidemic owing to the depletion of the health workforce. An extended version of this Correspondence can be found at http://documents.worldbank.org/curated/en/24652897. We declare no competing interests. No external funding was received for this work. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the World Bank and its affiliated organisations, nor those of the Executive Directors of the World Bank or the governments they represent. We thank Trina Haque, Patricio Marquez, and Shiyong Wang for their help in securing the data without which this work would not have been possible, as well as Kathleen Beegle, Timothy Bulman, Francisco Ferreira, and two anonymous reviewers for their suggestions. Supplementary Material Download .pdf (.4 MB) Help with pdf files Supplementary appendix Download .pdf (.4 MB) Help with pdf files Supplementary appendix