5 Health and WaSH
- Africa has historically experienced a high disease burden, which has contributed to low population densities in ancient times and curtailed development.
- Despite Africa’s continued high disease burden in modern times, countries in sub-Saharan Africa spend significantly less on health as a percentage of gross domestic product than regions elsewhere in the world.
- The HIV/AIDS and COVID-19 pandemics have had pronounced negative effects on Africa’s development with regard to economic productivity, mortality, life expectancy, and poverty reduction.
- Sub-Saharan Africa is forecast to achieve its epidemiological transition only around 2030, with rapid unplanned urbanisation and poor access to water, sanitation and health (WaSH) infrastructure having a noticeable negative impact on health and well-being.
- The Health/WaSH scenario simulates a combination of three sets of interventions to improve health outcomes in Africa, with concomitant improvements in poverty levels, disease burdens, infant mortality and life expectancy.
- Only 27 African countries will have full access to clean water by 2043, despite the significant push on WaSH infrastructure in this scenario. Yet the forecast underscores the imperative to design health programmes that extend beyond the health sector itself. Effective urban planning and a better understanding of the trade-offs in health policy versus investments such as providing basic WaSH infrastructure should lead to better outcomes.
The small group of our Homo sapiens ancestors, which eventually dominated the world, successfully migrated from Africa only some 70 000 years ago and eventually spread along the southern coast of Asia to Oceania and Europe.
Early humans gained an initial health reprieve when they moved out of Africa into cooler regions with fewer insect-borne diseases and ‘the many parasites and disease organisms that had evolved in parallel with the human species.’  As a result, humanity multiplied rapidly in these new areas until their large numbers required a more organised way of food production.
Less disease and the development of agriculture were key to humanity’s rapid growth. Higher population density, in turn, bred new diseases and also led to competition, and sometimes conflict, between people with regard to land, food and status, which required political organisation and further role differentiation. Competition spurred innovation and technological advancement. 
In contrast, large parts of ancient Africa’s interior were consistently characterised by low population densities due to the slow agricultural transition (see Agriculture in Africa), its geography and a high disease burden.
Vector-borne diseases, which are caused by parasites, viruses and bacteria and are transmitted to humans by mosquitoes, ticks and tsetse flies, are common in tropical and sub-tropical regions such as in Central Africa and places where access to safe drinking water and sanitation is limited. In temperate zones, such as much of Europe, parts of Asia and North Africa, the annual seasonal fluctuations serve as a natural constraint on the breeding cycle of vectors such as insects,  but in sub-Saharan Africa, this cycle is not similarly disrupted.
Archaeological findings indicate that vector-borne diseases have been endemic in large parts of Africa for thousands of years, which also prevented the use of the horse, ox or camel and so limited opportunities for more rapid progress.[ Today, 16 of the 30 countries listed by the World Health Organization (WHO) as having a high burden of tuberculosis are in Africa, although none are under the top five. [ ]] Malaria is particularly prevalent in Africa, with around 90% of cases and deaths occurring here. The continent also accounts for 34 of the 47 countries prone to yellow fever outbreaks and about 40% of the global burden of lymphatic filariasis (elephantiasis), both being diseases spread by mosquitoes in tropical areas. [ ]
At around 1 000 BCE, large populations (estimated at approximately 20 million people each out of a world population estimated at between 260 and 300 million) eventually appear to have grouped in five regions globally: China, the Indian subcontinent, Egypt, the Fertile Crescent  and Iran, and Europe. [ ] The sizable African continent, by contrast, had a much smaller population, perhaps even less than 20 million, half of which was by then concentrated in a single area along the fertile Nile Valley. [ ]
Although disease burdens in Europe and Asia were, on average, lower than in Africa, nature eventually reasserted itself into humanity’s new habitats outside of the continent as well. Most of today’s most prominent infectious diseases emerged only in the last 11 000 years, following the rise of agriculture. Larger settlements such as permanent villages and towns swept away the spatial limitation on the spread of disease. In particular, the introduction of domesticated animals such as dogs, pigs, cattle, horses and cats increased human exposure to infectious diseases spread mainly by rats and fleas. Indeed, COVID-19 (seemingly a zoonotic disease spread from bats to humans) is a potent example of this phenomenon. 
Largely because of its low population densities and the ability to continue with hunter-gatherer lifestyles, the technological developments that accompanied the Bronze Age and the Iron Age essentially bypassed much of sub-Saharan Africa. Owing to its relative isolation from global trade and conquest, Africa was also less affected by population bottlenecks (or near extinction events) such as significant famines, genocidal wars or the great plagues that affected the rest of the world, such as the Plague of Justinian, which reduced Eurasian populations by a quarter from CE 541 to 549. 
During the bubonic plague or Black Death that swept through Asia and Europe in the 14th century, between a quarter and two-thirds of the European population died. However, agriculture was a large enough driver of population growth and population numbers soon started to increase again. 
For a while, it seemed that the African civilisations that had developed in modern-day Ethiopia (such as Aksum) and in the west along the Niger River (such as the wealthy Mali Empire) could rival those elsewhere. South of the Sahara, the Bantu people had domesticated cattle and were growing sorghum and millet. They had also discovered iron, but they and other groups were not technologically advanced enough to resist external intrusion indefinitely.
However, because modern population densities (together with the density of domestic and farm animals) in modern times are so much higher in East and Southeast Asia, it is from there that most ‘zoonotic pathogens’ appear in recent history. Three-quarters of emerging human infectious disease outbreaks are zoonotic, meaning they originate from pathogens infecting animals that ‘jump’ species and infect people. 
In the last half of the 20th century, with the widespread use of antibiotics and vaccines, many people had begun to believe that the era of infectious disease was ending. However, the COVID-19 pandemic has shattered that belief, and in the past century, Asia and South America have also emerged as being of growing importance as origins of zoonotic pathogens.
West Africa in particular may become a hotspot of zoonotic pathogens, given the density of humans, poultry, pigs and ruminants. It is also clear that COVID-19 is not the last pandemic. The increase in human activity and its impact on the environment means that the frequency and severity of epidemics caused by wildlife zoonoses are increasing. A recent estimate  puts the probability of a future zoonotic spillover event resulting in a pandemic of similar magnitude as COVID-19 at 22%–28% in the next 10 years, and at 47%–57% in the next 25 years.
Sustainable Development Goal 3 speaks to ‘ensur[ing] healthy lives and promot[ing] well-being for all at all ages.’  Targets falling under this goal include:
- reducing maternal, infant and child mortality,
- ending the AIDS, tuberculosis and malaria epidemics, and
- reducing mortality from non-communicable diseases such as diabetes and cancer.
The ambitious targets set for this goal are unlikely to be reached by the 2030 deadline in most of the world. Although Africa has registered substantial improvements in a handful of targets (notably reducing AIDS-related deaths), the continent is likely to miss all the health-related sustainable development goal (SDG) targets, often by substantial margins. 
Countries in sub-Saharan Africa generally spend significantly less on health as a percentage of gross domestic product (GDP) than other regions globally (except for South Asia):
- Because of sub-Saharan Africa’s large young population, treating and preventing infectious diseases, such as influenza and mumps, requires less expensive treatments. In contrast, treating non-communicable diseases such as heart disease and diabetes, common among adult populations, is more expensive. These diseases are more prevalent in North Africa, with its moderately older population, with the region, on average, spending more than double per person on health compared with sub-Saharan Africa. Europe, with its much older population, spends several times more still per capita on health compared with North Africa. At US$2, providing a mosquito net to every vulnerable person in Africa every two years is far more affordable than ensuring that every African has reliable access to insulin (at an annual cost of more than US$300 per person), cancer screenings and dialysis.
- Low- and lower middle-income governments have less revenue to spend on health than upper middle- and high-income countries. On average, government revenue for low-income countries, most of which are Africa, are 12% of GDP and 20% for lower middle-income countries. In contrast, health expenditure amounts to 29% and 37% of GDP in upper middle-income and high-income countries, respectively. [ ]
- Sub-Saharan Africa has a higher disease burden than other regions.
HIV’s ancestor is the simian immunodeficiency virus (SIV), an infection of African monkeys that spread to chimpanzees and eventually to humans. SIV is several thousand years old and may even have been around millions of years ago.  The spread of SIV to humans is no surprise, with several major human infectious diseases all having made the interspecies jump. However, subsequent outbreaks historically did not cause severe epidemics in Africa as population densities were too low to sustain their spread. As a result, they died out.
However, as population sizes increased, there were eventually sufficient human hosts to allow SIV to survive and mutate. It eventually evolved into HIV, apparently first in the western equatorial region of Africa (today known as Cameroon and the Democratic Republic of Congo, DR Congo). During subsequent decades, subgroups of the virus were able to infect eastern, southern and western Africa.
The slow-acting, asymptomatic incubation period of HIV and the eventual appearance of diverse opportunistic infections defied prompt action until it had reached momentous proportions.  By the mid-1970s, HIV/AIDS was a true pandemic. HIV/AIDS remained silent and unrecognised for so long because it affects the immune system, meaning that people were dying from various opportunistic infections rather than from a single disease. It remained undetected because of Africa’s inadequate health systems, poor infrastructure and limited medical research capacity, and silently spread across the continent.
Even after HIV/AIDS was recognised as a major health threat, a lack of government capacity and the denialism of influential leaders such as President Thabo Mbeki of South Africa led to the unnecessary loss of hundreds of thousands of lives. In the country with the most significant AIDS death rate globally at the time, Mbeki’s stance would eventually contribute to his being ousted as president in 2008 in favour of a flawed replacement, Jacob Zuma.
AIDS is not the first modern pandemic,  yet its impact has likely been the most pronounced. Sub-Saharan Africa has suffered a tremendous toll. From 1998 to 2013, more than a million Africans died annually from AIDS and during the peak of the pandemic (2005–2006), more than 1.5 million each year. By 2019, almost 32 million Africans succumbed to the disease.
The AIDS pandemic dramatically impacted on health outcomes, particularly in South Africa, Nigeria, Tanzania, Uganda, Kenya, Zimbabwe, Ethiopia, Mozambique Malawi and Zambia (see Chart 1). It had a serious effect on economic productivity and a disastrous impact on families and communities. Life expectancy in these countries fell precipitously and has not recovered to the pre-AIDS trajectory.
The impact of AIDS on life expectancy can be seen in Chart 2. Before AIDS, life expectancy in Southern Africa was significantly above that in East, West and Central Africa, but by 2004 it was below all three and is now on a similar trajectory to Central Africa. Life expectancy in North Africa, which was not substantially affected by AIDS, is comparable with the global average.
Since the peak of the AIDS pandemic in 2005/06, improvements in treatment (particularly in the mass roll-out of antiretrovirals) and prevention have reduced the impact of the disease. Life expectancy has consequently partially recovered but it has still not caught up with the rest of the world. By 2019, the gap in life expectancy between sub-Saharan Africa (64.2 years) and the global average (73.2 years) was nine years. Life expectancy was at almost 70 years in South Asia and 76.6 years in South America.
HIV/AIDS dealt sub-Saharan Africa a devastating blow. It came at a time when the continent had shown signs of a turnaround from the declining economic growth prospects in the 1980s and 1990s. This change in fortune was the result of various factors examined in the Current Path theme, including a determined effort by some in the international community to place poverty alleviation at the core of global concerns with the end of the Cold War. Its impact continues to linger, with 77% of AIDS deaths globally in 2019 occurring in sub-Saharan Africa.
Whereas HIV/AIDS had a dramatic impact on life expectancy, the economic impact of the COVID-19 pandemic far outweighs its effect on mortality. Compared with HIV/AIDS, recorded mortality due to COVID-19 in Africa is low (although the disease has not entirely run its course). Although the associated data is incomplete, the mortality rate relative to total population in Africa appears to be lower than in the Americas, Europe and even, marginally, Asia. 
The UN described the impact of the COVID-19 pandemic as ‘the greatest test that we have faced since the formation of the United Nations.’ The International Monetary Fund (IMF) categorised it as ‘the worst economic fallout since the Great Depression.’  Globally, trillions of US dollars have been committed to fighting both the direct and indirect effects of the pandemic. By September 2021, the US alone has spent and allocated more than US$8 trillion and, by some estimates, much more. [ ]
The pandemic spread particularly rapidly in South Africa, which had the most significant number of reported cases and deaths on the continent. [ Other highly affected countries include Tunisia, Egypt and Morocco. Low mortality does not necessarily mean low infections, but rather that Africans were less likely to succumb to the disease. [x] Then, as vaccination rates elsewhere ramped up, Africa’s mortality rate inevitably increased. [ ]]
Africa’s youthful population seems the most likely explanation for low mortality. The virus affects older people more seriously, resulting in higher levels of morbidity and mortality. Other possible contributing factors include:
- low levels of urbanisation, which may provide rural people with protection against the rapid spread.
- climatic and seasonal impacts (although these are still speculative).
- lower rates of obesity, diabetes and other non-communicable comorbidities than in developed countries.
- a tuberculosis vaccine routinely given to children in many African countries may have reduced the likelihood of deaths from COVID-19. [ ]
- the public health response to COVID-19, along with measures such as mask mandates and lockdowns, having been less politicised than in Europe and North America. [ ]
- prior exposure to other coronaviruses, including those that cause the common cold, providing a degree of resistance in some of the very communities once thought to be most vulnerable. [ ]
However, data on COVID-19 in Africa needs to be treated with caution. Similar to the case with HIV/AIDS, a large portion of COVID-19 deaths are unreported, reflected in the calculations released by The Economist, [ amongst others. A further issue is that Africa (and much of the rest of the developing world) is vaccinating extremely slowly, initially because of a lack of vaccines. Africans may therefore remain vulnerable to the disease long after the rest of the world has transitioned out of the pandemic state. African leaders, including the South African and Kenyan presidents, have spoken out against what they call ‘vaccine apartheid’, [x] and there are fears that Africans could be stigmatised and excluded from international travel and business while they wait for vaccination even as the rest of the world moves on.]
Vaccination inequity creates perfect conditions for the evolution of a new, possibly vaccine-resistant strain (which could undo the vaccination efforts in the rest of the world). This has led to calls for intellectual property restrictions concerning vaccine development to be waived so that vaccine production can be boosted in developing countries to somewhat equalise its distribution. The US belatedly indicated its support for the move, although it remains to be seen whether this support will translate into practical results, especially with other key countries, such as Germany, opposing the request. 
The impact of COVID-19 is overwhelmingly economic in nature. As shown in Chart 3, COVID-19 will condemn millions more Africans to extreme poverty and incomes will decline. Using GDP per capita as measure, the Current Path forecast shows that Africa will likely return to its 2019 average only by 2025. Many will succumb to a lack of food as the efforts to constrain infection rates reduced economic activity and job security. Eventually, more Africans may die of the secondary effects of COVID-19, such as reductions in treatment available for other diseases due to health spending being diverted to combat COVID-19, than from the virus itself. The associated global recession hit Africa very hard, particularly given the commodity dependence of many of its economies. The result is that growth and economic improvements are constrained.
In addition, the economic impact of COVID-19 has reduced government revenues (by US$61 billion in 2020, and slightly lower annual amounts since), meaning less money is available for providing security, building schools, and developing infrastructure and healthcare services. The result has been an increase in instability, riots and protests.
The world will eventually learn to live with COVID-19, much like it has learnt to live with HIV/AIDS and the additional security that disrupted international travel after 9/11. The pandemic has, however, also had many other effects, including greater awareness of global interdependence and the rise of remote work and a change in how we spend leisure time. It has boosted the service sector and underlined the importance of food security. It may also slightly delay Africa’s imminent epidemiological transition.
The typical evolution of the disease burden over time is that countries first experience a declining burden of infectious diseases and later an increased incidence of non-communicable diseases — that is, lifestyle diseases typical of older, sedentary population cohorts and those who consume processed foods. This is the switch from death in childhood to death in old age.
The so-called epidemiological transition occurs when improved food security and innovations in public health and medicine result in infectious (or communicable) diseases, such as influenza, being replaced as the dominant cause of death by chronic conditions, such as cancer. This change is generally associated with the transition from developing to developed nations.
In Europe and North America, the transition from communicable to non-communicable diseases as the leading cause of death occurred more than a century ago. In Latin America and the Caribbean, it happened around 1970, in North Africa around 1980 and in South Asia around the start of the current century; yet it is set to occur in sub-Saharan Africa only around 2030 (Chart 4).
With a median age below 19 years, populations in sub-Saharan Africa experience a much higher infectious (communicable) disease burden than a non-communicable disease burden because children are especially susceptible to the former. Poor living conditions, including unsafe water, poor housing and inadequate sanitation, also create an environment conducive to the spread of disease.
In more densely populated parts of the world, the rise of large cities required authorities to implement proper sewage systems and other measures to combat infectious diseases. The epidemiological transition in Western Europe and North America was largely as a result of infrastructure investments, such as closed sewage systems and clean water supply by public utilities in the 19th century, and later by vaccines and the discovery of penicillin. But by the time Africa started to become more urbanised (towards the end of the 19th century), imported modern medicine (vaccines and antibiotics) allowed for higher population densities without the need to invest in the associated health infrastructure. Larger communities of people were now able to live in larger settlements, not because of city planning or appropriate housing laws, adequate municipal water and sewerage infrastructure, as was required elsewhere to contain disease and plague, but because modern medicines served as an effective alternative to keep infectious diseases under control. 
In Africa, the poor generally move to cities without the prospect of a job or an improved lifestyle to escape the destitution in rural areas. Africa is also urbanising much later than other regions, and this is now happening quite rapidly. The result is massive increases in large, sprawling slum cities that do not have clean water or adequate sewage systems, some of which are already evident in places such as Lagos, Dar es Salaam and Nairobi.
According to the Current Path forecast, sub-Saharan Africa only becomes predominantly urban by around 2040 (Chart 4) and will be the most rural continent in the world, although the absolute increase in growth of the urban population is large.
The continent’s urban population is forecast to more than double by 2043, adding more than 800 million people to Africa’s towns and cities. The UN Population Division (UNPD) anticipates that between 2018 and 2035 all ten of the world’s fastest-growing cities will be in Africa — and 21 of the top 30.  Twelve of these are in West Africa, four of which are in Nigeria. The four Nigerian cities alone are projected to add about 200 million people to urban areas in Africa by 2050 compared to 2020.
Yet Nigeria is likely to still have about 37% of its massive population in rural areas in 2043. The most urbanised countries in Africa will be Botswana, South Africa, São Tomé and Príncipe, Algeria, Djibouti, Libya, Equatorial Guinea and Gabon, although most of these countries are already highly urbanised. Ethiopia, Kenya, Burkina Faso, Mali, Tanzania and Madagascar all have urbanisation levels under 45% today, but this number will increase by between 12 and 16 percentage points by 2043. These countries are of low-income status or have a large current population (over 50 million people today), or both (in the case of Ethiopia), suggesting that their exploding cities will present major challenges to policymakers who have few resources to provide infrastructure for their already large populations.
Several African cities are already known for their slums. Slums and informal townships present a number of problems, largely because they develop in the absence of planning. Housing units are almost exclusively self-constructed and neighbourhoods are organised independently of the central governing authority.
Africa has poor sanitation and limited access to safe water, making it potentially more susceptible to the impact of new viruses such as COVID-19. The simple but essential act of washing one’s hands is difficult without consistent and reliable access to clean water.
In much of Africa, basic sanitation infrastructure is inadequate and often non-existent in rural areas. In 2019, only 78% of Africa’s population had access to improved water supply compared with 96% in the rest of the world. This situation will slowly improve. By 2030, approximately 82% of Africans are likely to have access to improved water supplies. The SDG target is for 98% of the population in all countries to have access to improved sanitation services but is it likely that this will be possible for less than 64% of people. Only about 22% of the population are expected to have access to wastewater collection or treatment systems. By 2030, only seven countries (Algeria, Tunisia, Botswana, Seychelles, South Africa, Libya and Morocco) will be above the average for wastewater connections in the rest of the world (the world except for Africa), which will be at 56%.
Modern medicine means that people in sub-Saharan Africa are now living long enough to succumb to non-communicable afflictions. There are now many older people in poor countries contracting the ‘diseases of affluence’, despite the presence of a large youthful population that keeps the country’s median age relatively low. In sub-Saharan Africa, the transition is happening at lower levels of income and urbanisation than elsewhere. Because the burden of communicable diseases also remains high, Africa suffers from a so-called double burden of disease — a high rate of deaths from both communicable and non-communicable diseases, which will present health systems in much of Africa with steadily worsening costs as they navigate increasingly complex public health landscapes. Africa’s comparatively low average incomes translate into limited state budgets and capacity to provide the necessary healthcare for the treatment of non-communicable diseases.
The result of the approaching double burden of disease will be more sick adults, requiring more resources to prevent and treat costlier non-communicable conditions. Pollution and tobacco are also proving to be a considerable challenge, as tobacco companies are now actively targeting the next generation of smokers, all of whom are in the developing world.
Still, communicable diseases continue to have a disproportionate and devastating impact on Africa:
- In 2019, almost 91% of malaria deaths worldwide occurred in Africa.
- About 78% of HIV/AIDS deaths occur in Africa.
- The continent accounts for nearly 50% of all infectious disease deaths worldwide, despite making up only 17% of the global population. This means people in Africa are about 4.5 times more likely to die from a contagious disease than people elsewhere.
Chart 6 presents death rates as a percentage of total deaths for the three major categories used to determine the Global Burden of Disease (communicable disease, non-communicable disease and injuries) for Africa compared with the rest of the world in 2019 and 2043. 
Although having declined substantially in the intervening years, Africa’s current high communicable disease burden is still likely to constitute 27% of deaths by 2043 compared with 6% in the rest of the world.
This trend is forecast to continue beyond 2043 in the Current Path, when Africa is projected to account for about 93% of global malaria deaths, 80% of global AIDS deaths and almost half of total communicable disease deaths worldwide. It is partly because of this disease burden that the current average life expectancy at birth in Africa (66 years) is so much lower than that in the rest of the world (75 years) and is also forecast to remain significantly below global averages beyond the 2043 time horizon.
However, these trends vary hugely between countries:
- By 2043, only six African countries will have a proportion of communicable deaths below the 6% average in the rest of the world, namely Libya, Tunisia, Mauritius, Morocco, Egypt, and Algeria. Even high-income Seychelles is likely to have 9% of its deaths caused by communicable diseases.
- On the other end of the spectrum, Chad, Nigeria, South Sudan and Angola will still see at least 40% of the deaths in their countries caused by communicable diseases. This may be understandable in Chad and South Sudan, two of Africa’s poorest countries, but it is more disturbing when looking at oil-rich Angola and Nigeria. Despite being an economic heavyweight, Nigeria will continue to have a large and youthful population in the future, as well as sprawling megalopolises, making the universal provision of basic water and sanitation increasingly difficult.
Addressing Africa’s disproportionate communicable disease burden is a high priority, but any progress in this regard will inevitably mean a greater prevalence in non-communicable causes of morbidity. Africa’s epidemiological transition will hence occur at a point when incomes are still quite low compared with those in countries that have already gone through the transition.
Non-communicable diseases are more difficult and expensive to diagnose, treat and manage than communicable diseases, and many health systems will likely struggle to respond effectively. In fact, more than one-third of all deaths in sub-Saharan Africa are already categorised as non-communicable, a share that is forecast to rise to more than 63% by 2043, even in the absence of additional interventions.
Africa approaching its epidemiological transition with a severe lack of essential services such as clean water and proper sanitation presents a significant health challenge. Access to water, sanitation and hygiene (WaSH) serves as a helpful proxy for a government's ability to fulfil the basic needs of its people and access to safe water has therefore been declared a basic human right. 
In 2019, only about 57% of the continent had access to an improved sanitation facility, while the average for the rest of the world was approximately 87%. For clean water, the rates are only slightly improved, with about 78% of people in Africa having access compared with more than 96% in the rest of the world. In comparison, about 74% of people in South Asia had access to an improved sanitation facility in 2019, and about 95% of the region had access to potable water.
The picture is similar to nearly any other measure of access to infrastructure or services. For example, in 2019 about 95% of global populations outside of Africa had access to electricity. In Africa, the figure was approximately 53% (and 45% in sub-Saharan Africa), compared with 87% in South Asia. The use of solid fuels for cooking and heating instead of electricity is also a large source of indoor air pollution with all kinds of health complications. This lack of access to physical infrastructure and basic services constrains Africa’s ability to fully develop its human potential and thus to capitalise on its future demographic dividend.
Partly as a result of these differences, people in South Asia can expect to live about six years longer at birth and receive more than a full year of additional education relative to their counterparts in sub-Saharan Africa. At 50 infant deaths per thousand live births, infant mortality in sub-Saharan Africa is about 45% higher than in South Asia and 350% times higher than in South America.
WaSH infrastructure supports the development of broader human potential through its strong forward linkages to other important aspects of the SDGs, such as poverty, education and gender equality. Improved WaSH infrastructure generally translates into sizable gains in the overall development of a country as it improves the human capital contribution to economic growth.
For example, children who do not have adequate access to WaSH facilities are more vulnerable to undernutrition. Malnourished children are not only highly susceptible to communicable diseases, with diarrhoeal diseases being among the most frequent and severe examples,  but may also suffer other lifelong effects such as stunting (low height for age). [ ]
Stunting impairs both physical and cognitive development. According to the WHO, stunted individuals suffer from ‘poor cognition and educational performance, low adult wages, lost productivity and, when accompanied by excessive weight gain later in childhood, an increased risk of nutrition-related chronic diseases in adult life.’  Put bluntly, stunting is an irreversible condition that inhibits the potential of the affected individual or community for life. Although the overall rate in sub-Saharan Africa is ‘only’ about one-fifth (with only a very modest decline forecast to 2043), about one-third of children below 5 years are stunted.
Insufficient WaSH access leaves all children vulnerable, but as they mature, the negative impacts begin to stack up disproportionately against women and girls. Poorly maintained or non-existent WaSH facilities are one of the main causes of the high rate of school dropout among teenage girls, who lack menstrual hygiene services for example.  This, in turn could lead to a large disparity among educational attainment between men and women and significantly diminish the economic opportunities for women, translating to lower growth for society as a whole.
There are immense challenges to advancing access to WaSH infrastructure in sub-Saharan Africa.  Even upper middle-income countries in Africa are struggling to expand access to WaSH infrastructure, in particular sanitation facilities, fast enough. Of Africa’s seven upper middle-income countries, only Libya, Mauritius and South Africa registered access to improved sanitation rates above the global average for countries in this category (about 88%).
In the four other countries (Namibia, Botswana, Equatorial Guinea and Gabon), about 9 million people were still living without access to an improved sanitation facility in 2019. It is likely no coincidence that three of these four countries, namely Namibia, Botswana and Equatorial Guinea, rank among the most unequal countries in the world according to the Gini index.
In the Current Path forecast, only 42% of sub-Saharan Africa’s population is projected to have access to an improved sanitation facility by 2030 and just over 80% is forecast to have reliable access to clean drinking water. Although almost 88% of the population in sub-Saharan Africa is set to have access to improved water in 2043, it is still ten percentage points short of the 98% 2030 SDG target. Similarly, despite improved sanitation projected to be available to 58% of the population — a vast improvement from the current figure — it is far from the 2030 goal of near universal access.
In 2019, 224 million people in the DR Congo, Ethiopia and Nigeria alone were living without access to improved sanitation facilities. This number is projected to increase to about 255 million by the time the SDGs are meant to be achieved (2030). It will likely decline to 159 million in 2043, with much of that improvement from Ethiopia only. Nigeria’s rapid population growth will continue to put pressure on basic infrastructure, as it will have 109 million people without sanitation in 2043 compared with 101 million in 2030. Despite their massive economic potential, these large populations seem likely to suffer from a lack of proper sanitation for the foreseeable future, and even Ethiopians will have to wait for decades for their expected improvement.
Although a coordinated cross-sectoral approach is necessary to overcome the negative impact of poor health outcomes on development in Africa, a push on the most immediate health and infrastructure priorities will have significant and visible effects on outcomes such as infant mortality and life expectancy. A healthier population will also be more productive and, once combined with better education and other enablers, improve economic growth prospects significantly.
Given how far behind Africa is on these indicators compared with other regions, the interventions in our Health/WaSH scenario are not calibrated to represent Africa achieving the respective SDGs by 2030. Rather, they reflect a determined and ambitious push against what was historically achieved in South America and South Asia, the two regions most comparable to Africa.
The Health/WaSH scenario (Chart 9) simulates a combination of three sets of improvements:
- More rapid provision of basic infrastructure (clean water and improved sanitation), which particularly pushes on the drivers of Africa’s high communicable disease burden as well as indirectly on improving productivity given a generally healthier workforce. [ ]
- Large reductions in the incidence of HIV/AIDS and malaria in the countries most affected by these diseases on the back of expectations regarding rapid progress in prevention and treatment. Mortality is also reduced in countries with high levels of respiratory infections, respiratory diseases and the category of ‘other communicable diseases’.
- Modest reductions in the incidence of non-communicable diseases, namely diabetes, malignant neoplasm, cardiovascular diseases, in most highly affected countries, and the category of other non-communicable diseases, also based on ongoing improvements in medical technology.
The earlier and more rapid improvement in access to safe water proposed by the Health/WaSH scenario is almost two percentage points above the 2043 Current Path forecast (Chart 10). Improved sanitation is six percentage points higher in 2043 than in the Current Path forecast.
The Health/WaSH scenario represents an ambitious push on the poorest countries (Chad, South Sudan and Madagascar, which are the least connected to improved sanitation in the Current Path), translating to improvements of 45%–55% by 2043.
The interventions on the incidence of malaria and HIV/AIDS in the Health/WaSH scenario are particularly aggressive and imply large advances in treatment through the expected development of vaccines.  The effect is that 285 000 fewer Africans will die from malaria and 132 000 fewer from AIDS by 2043, respectively roughly 70% and 40% less than in the Current Path forecast. Cumulatively, 5.5 million fewer people will succumb to malaria and 3 million fewer to AIDS from 2024 to 2043. Advances in medical science may also help to overcome the threat of malaria drug resistance in Africa. [ ]
The scenario also results in a 13% reduction in the broad category of ‘other communicable diseases’ by 2043, which exclude diarrhoeal diseases, HIV/AIDS, malaria and respiratory infections.
Already in the Current Path forecast, a number of countries (e.g. Ethiopia, the Republic of Congo and Togo) expect substantial improvements in the provision of sanitation by 2043. Chart 11 illustrates the progress on the Current Path by 2043 and further improvements as a result of the Health/WaSH scenario. The data in the chart is sorted in descending order, using percentage of access to improved sanitation in 2019. A segment representing the progress by 2043 in the Current Path is added, and then, on top of that, another segment that represents the improvement from the Health/WaSH scenario by 2043 for each country.
Despite aggressive improvements (more than 50 percentage points) forecast for Togo, Sierra Leone, Central African Republic, Malawi, Guinea Bissau and Liberia between 2019 and 2043, these will come too late for the present generation. The majority of low-income countries in Africa will not even achieve 50% coverage by 2030. Disappointedly, Africa’s most diversified economy, South Africa, is forecast to experience an improvement of only two percentage points over the forecast horizon and will be unable to reach full access by 2043, showing very little improvement compared with its peers. This represents a lost opportunity and, perhaps, poor allocation and management of resources.
The Health/WaSH scenario is also projected to bring 6.7 million Africans out of poverty (using the US$1.90 extreme poverty line) in 2043 compared with the Current Path. This figure includes 1.3 million each in the DR Congo and Nigeria, and 700 000 in Kenya.
Health costs decline in the Health/WaSH scenario, but infrastructure costs increase by a larger margin. Cumulatively, African governments will spend US$20 billion less on health from 2023 to 2043, as medical breakthroughs with regard to AIDS and malaria reduce costs. However, the required investment in WaSH infrastructure is more than double the savings (total cumulative cost US$57 billion). On average, the GDP per capita improves by a modest amount (US$68 in 2043) compared with the Current Path forecast. Some countries, such as Equatorial Guinea, Eswatini and Namibia achieve a larger increase while a few countries experience a decline because of the requirement for infrastructure (e.g. Mauritius will be the most affected, with a decline of US$82 in 2043). These results reflect the long time for investments in health to translate to economic improvement, often impacting on successive generations rather than the effects being seen within a decade or less.
Africa will experience an increase of 0.1% in its average GDP growth rate between 2024 and 2043, with the result that the African economy will be US$143 billion larger in 2043 than in the Current Path forecast.
Even with the significant push on WaSH infrastructure in this scenario, Africa will not have reliable access to clean water by 2043. At that point, 208 million Africans will still depend on water connections that do not adequately protect the water source from contamination, in particular faecal matter.
About 1.6 billion Africans will be connected to improved sanitation services by 2043, with 269 million still using shared sanitation and 377 million relying on ‘unimproved’ sanitation facilities such as open pit and bucket latrines. Although the continent will not achieve the 2030 SDG target, a push to combat communicable diseases and improve WaSH infrastructure would still have significant benefits for human and economic development.
Technological advances will undoubtedly help the drive for improved basic infrastructure at a lower cost. For example, since 2011, the Bill and Melinda Gates Foundation has invested more than US$200 million in the ‘Reinvent the Toilet’ challenge. Among the early successes was the Tiger Toilet, which costs about US$350 to install and requires no traditional sewer system. Instead it uses Tiger worms (Eisenia fetida), which feed on human faeces. Once a person has used the toilet, they flush their waste down into the worm-filled compartment below using a small bucket of water. The process removes 99% of pathogens and leaves behind no more than 15% of the waste by weight, much better performance than a septic tank. The leftover product is also an excellent fertiliser. After five years, the first Tiger toilets have yet to require maintenance. The market for this new toilet technology is estimated to amount to US$6 billion a year by 2030, more than the current GDP of 16 African countries. 
Another way of measuring the impact of the Health/WaSH scenario is to use disability-adjusted life years (DALYs), a standard metric for capturing a country or region’s disease burden. This metric offers a way of accounting for the difference between a current situation and an ideal situation, where everyone lives up to the life expectancy in Japan (the country with the longest life expectancy globally), free of disease and disability. Early death translates to years of life lost while sickness translates to years lost due to disability. One DALY therefore represents the loss of the equivalent of one year of full health. 
For example, in 2019 Africa is estimated to have lost around:
- 351 million years of life as a result of its high communicable disease burden.
- 218 million years as a result of non-communicable diseases.
- 47 million years due to injuries. [ ]
In the Health/WaSH scenario, Africa gains 40 million DALYs in 2043 from a lower communicable disease burden and almost 4 million years from a lower non-communicable disease burden (Chart 12). In addition to the intrinsic value of healthy human life, this also means millions more productive years and contributions to the continent’s development.
Africa is already on its way to reducing infant mortality significantly from its 2019 average: from 46.8 deaths per 1 000 live births to 37.8 by 2030 and 25.6 by 2043. The Health/WaSH scenario shrinks those numbers by almost 10% (to 34.7 deaths per 1 000 live births in 2030 and 22.6 per 1 000 live births by 2043), respectively. The reduction in country-level rates is presented in Chart 13. Libya gains the least by 2043 and South Sudan the most, followed by Nigeria, Chad and Madagascar.
Because of reduced infant mortality, the number of births start declining from around 2026 as society reacts to the fact that more infants are surviving. By 2043, Africa would cumulatively have 15 million fewer births, and the total population of the continent will be about 7 million people less than projected by the Current Path forecast for that year.
Chart 14 shows the expected life expectancy in Africa, with trends for South Asia and South America added for comparison. In the Current Path forecast, life expectancy in Africa is projected to improve from 65.8 years in 2019 to 72.1 years in 2043. In the Health/WaSH scenario, life expectancy increases to 72.8 years. Lesotho gains the most (an increase of more than 2.2 years), followed by South Africa, Nigeria, South Sudan and Chad. The countries that gain the least are Comoros, Djibouti and The Gambia, with the latter gaining only 6 months.
This theme started by briefly explaining the historical context for Africa’s continued high disease burden. It included an analysis of the impact of the most serious epidemics — HIV/AIDS and COVID-19 — on Africa and examined the positive impacts of modern medicines (that partly obviate the requirements for functioning basic infrastructure), and the negative impacts of under-resourced and poorly designed health systems.
The COVID-19 crisis has delayed the world in achieving the targets of the SDGs, as substantial public resources have been diverted away from primary development priorities in fighting the virus. Moreover, the pandemic has rudely exposed the dismal state of Africa’s health and associated systems. Currently, the continent imports 99% of its vaccines from abroad and its ability to respond to future pandemics through research and manufacturing of vaccines is abysmal, although initiatives to increase local vaccine manufacturing are getting off the ground. 
It is likely that we underestimate the relationship between health and economic growth, but the inclusion of infrastructure in the Health/WaSH scenario already underscores the imperative to design health programmes that extend well beyond the health sector itself. In Africa, providing basic infrastructure such as WaSH facilities and household electricity reduces the impact of diarrhoeal and vector-borne diseases, as well as the respiratory harm caused by indoor use of traditional fuels like dung and charcoal. There is also a role for the international community although, as we explore elsewhere, aid is no panacea. Installing taps and toilets has historically not been as attractive to donors (and sometimes governments) as, say, eliminating river blindness, but it will have a tremendous impact on livelihoods on the continent if foreign aid providers could serve to spur African governments to place more emphasis on WaSH and related infrastructure.
Demographic growth and technological change can work in Africa’s favour, but deferred action will be extremely costly. Delays or poor urban planning will result in larger and more dangerous unplanned urban spaces. Urban planning in Africa must emphasise the provision of basic infrastructure, such as clean water, improved sanitation facilities and household electricity, as well as increasing access to and the general quality of health and education services.
Africa’s health systems are desperately trying to battle the world’s worst communicable disease burden with rising rates of non-communicable diseases. This emerging double burden of disease is a complex challenge with many moving parts, but a better understanding of the trade-offs in health policy versus investments like providing basic WaSH infrastructure should lead to better outcomes.
Against this background, getting more rapidly to Africa’s demographic dividend and improvements in education may be among the most important drivers of better health in much of Africa. Awareness and information programmes can contribute greatly to communicating the benefits of good hygiene and preventing the spread of communicable diseases like HIV/AIDS and diarrhoea. They can also instil healthy, lifelong habits around the importance of exercise and good eating, which could help to prevent or at least delay the onset of non-communicable diseases that are expensive to treat, such as type-2 diabetes and heart disease.
J Reader, Africa: A Biography of the Continent, New York: Penguin, 1998, 234
J Diamond, Guns, Germs and Steel: The Fates of Human Societies, New York: W.W. Norton & Company, 2015, 386.
ND Wolfe, CP Dunavan and J Diamond, Origins of major human infectious diseases, in Improving Food Safety Through a One Health Approach: Workshop Summary, Institute of Medicine, Washington: National Academies Press, 2012; see also: J Reader, Africa: A Biography of the Continent. New York: Penguin, 1998, 242.
C Aydon, A Brief History of Mankind: An Introduction to 150,000 years of Human History, Philadelphia: Running Press, 2009, 125.
This includes Iraq, Israel/Palestine, Syria, Lebanon, Egypt and Jordan, as well as the south-eastern fringe of Turkey and the western fringes of Iran.
C Aydon, The Story of Man, Philadelphia: Running Press, 2007, 71.
World Health Organization, Global tuberculosis report 2018, Geneva: World Health Organization, 2018.
ND Wolfe, CP Dunavan and J Diamond, Origins of Major Human Infectious Diseases, Nature, 447: 2007, 279–283. At the time of writing, the origins of COVID-19 were not fully clear, but apparently it is a recombination of two different viruses, likely from bats and pangolins, that had simultaneously infected the same organism and from there, infected and spread among humans — see: A Hassanin, Coronavirus origins: Genome analysis suggests two viruses may have combined, World Economic Forum, 2020
Regions isolated from Eurasian plagues, such as Japan, Central and South America and parts of sub-Saharan Africa did not suffer the same fate.
SA Alchon, A Pest in the Land: New World Epidemics in a Global Perspective, Albuquerque: University of New Mexico Press, 2003, 21. The third, much more recent plague in the late 19th and early 20th century, was largely confined to Asia.
B Bett, D Randolph and J McDermott, Africa’s growing risk of diseases that spread from animals to people, IFPRI blog, 2020
From Metabiota, as presented at a seminar ‘What’s Next? Predicting the Frequency and Scale of Future Pandemics’, 20 July 2021, Center for Global Development.
United Nations, Department of Economic and Social Affairs, Sustainable Development
There are exceptions, of course. Private healthcare in South Africa is among the best globally, although expensive and thus only available to a small portion of the population. Only four African countries — Mauritius, Tunisia, Seychelles and Libya — are set to meet the 2030 target to reduce infant mortality to less than 12 deaths per 1 000 newborns.
When the contribution of aid is factored in, these numbers change. Expenditure increases to 20% and 21% in low-income and lower middle-income countries, respectively (receiving most aid), 29% in upper middle-income countries (they do not receive aid and are generally not aid providers), and 33% in high-income countries (as they are aid providers).
PM Sharp and BJ Hahn, The Evolution of HIV-1 and the Origins of AIDS, Philosophical Transactions of the Royal Society B: Biological Sciences, 365:1552, 2010, 2487–94
J Iliffe, The African AIDS Epidemic: A History, Oxford: James Currey, 2006, 4–5, 158–159.
Spanish influenza killed 40–50 million people in 1918, Asian flu killed 2 million people in 1957, and Hong Kong influenza killed 1 million people in 1968.
Our World in Data, Coronavirus (COVID-19) deaths, 2021
United Nations, UN launches COVID-19 plan that could ‘defeat the virus and build a better world’, 31 March 2020; Speech by: Kristalina Georgieva, Confronting the crisis: Priorities for the global economy, Washington DC: International Monetary Fund, 2020
USASpending, The Federal Response to COVID-19, 31 December 2021; N Sherman, Biden’s Covid stimulus plan: IT costs $1.9tn but what’s in it?, BBC News, 6 March 2021; Committee for a Responsible Federal Budget, COVID Money Tracker, 2021
Our World in Data, Coronavirus (COVID-19) deaths, 1 September 2021
E Stoltz, Sub-Saharan Africa children show higher Covid-19 death rate than elsewhere, Mail and Guardian, 21 January 2022
LE Escobar, A Molina-Cruz and C Barillas-Mury, BCG vaccine protection from severe coronavirus disease 2019 (COVID-19), Proceedings of the National Academy of Sciences of the United States of America, 28 July 2020, 117:30, 17720–25
A Baker, Why Africa’s COVID-19 outbreak hasn’t been as bad as everyone feared, Time, 30 December 2020
BA Marzoog and TI Vlasova, The Possible Puzzles of BCG Vaccine in Protection against COVID-19, Egypt J Bronchol, 15:1, 2021, 7
S Wild, Hidden toll of COVID in Africa threatens global pandemic progress, Scientific American, 25 March 2021
BBC News, COVID: US backs waiver on vaccine patents to boost supply, 6 May 2021
TJ Bollyky, Plagues and the Paradox of Progress: Why the World Is Getting Healthier in Worrisome Ways. Cambridge: MIT Press, 2018.
The Institute for Health Metrics and Evaluation (IHME) at the University of Washington maintains the database. In 2019, it represented 286 causes of death, 369 diseases and injuries and 87 risk factors in 204 countries and territories over time.
United Nations, General Assembly resolution 64/292, The human right to water and sanitation, A/64/L.63/Rev.1 and Add.1 (28 July 2010), 2010, www.un.org/en/ga/search/view_doc.asp?symbol=A/RES/64/292.
The United Nations Children’s Fund (UNICEF) estimates that of the roughly 1 600 child deaths due to diarrhoeal disease each day, about half are attributable to a lack of WaSH access. In recognition of this, the World Health Organization and UNICEF’s Joint Monitoring Project recognise access to WaSH facilities as ‘fundamental to good health, dignity and quality of life.’ See: UNICEF, How WASH relates to health, education and development, 2015; WHO/UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene, WASH Post-2015: Proposed Targets and Indicators for Households, Schools and Health Centers, Washington: JMP, 2012.
Stunting is defined as a child’s height-for-age ratio being more than two standard deviations below the World Health Organization’s Child Growth Standards median. WHO, WHO Child Growth Standards Length/height-for-Age, Weight-for-Age, Weight-for-Length, Weight-for-Height and Body Mass Index-for-Age: Methods and Development, Geneva: WHO Press, 2006.
World Health Organization, Stunting in a nutshell, 2015
A study from Malawi, for example, found that only 46% of girls who reached menarche before age 14 completed primary school, compared with 70% who reached it after 16 years of age due to a lack of appropriate menstrual hygiene management resources. M Sommer, Menarche: A Missing Indicator in Population Health from Low-Income Countries, Public Health Report, 128:5, 2013, 399–401. In many instances, women and girls also face an increased risk of sexual assault when using these facilities at night, in part due to the absence of decent lighting. A 2015 study in Khayelitsha (South Africa) by Yale University found that simply increasing the number of toilets could lead to a reduction in sexual violence against women and girls. When the ‘social cost’ of sexual violence — including tangible costs such as medical expenses, legal adjudication and correctional time, as well as intangible costs such as trauma and risk of homicide — is taken into account, erecting more toilets could actually save costs, too. GS Gonsalves, EH Kaplan and AD Paltiel, Reducing Sexual Violence by Increasing the Supply of toilets in Khayelitsha, South Africa: A Mathematical Model, PloS ONE, 10:4, 2015, e0122244
See: A Markle and Z Donnenfeld, Refreshing Africa’s Future: Prospects for Achieving Universal WASH Access by 2030, African Futures Paper, 2016, Institute for Security Studies.
Infant mortality is defined as the death of an infant before their first birthday. The rate is typically expressed as the number of infant deaths for every 1 000 live births.
The intervention reduces the proportion of people that have unimproved water access. The IFs algorithm then allocates the improvements to other improved and piped water.
Large-scale trials on two vaccines to protect against HIV were already underway by the end of 2020, raising hopes of an end to the epidemic (see: S Okiror, Africa steps up fight against HIV with trial of new combination vaccines, The Guardian, 18 December 2020). Similarly, a candidate vaccine against malaria (R21/Matrix-M, developed at the University of Oxford) was reported in 2021 to show up to 77% efficacy in a year-long trial that involved 450 children in Burkina Faso (see: K Kelland, Potential new malaria vaccine shows promise in Burkina Faso trial, Reuters, 23 April 2021).
See: S Boseley, Scientists sound warning note over malaria drug resistance in Africa, The Guardian, 15 April 2021
H Brueck, A $350 toilet powered by worms may be the ingenious future of sanitation that Bill Gates has been dreaming about, Insider, 13 January 2019
CJ Murray and AD Lopez, Global Mortality, Disability, and the Contribution of Risk Factors: Global Burden of Disease Study, Lancet, 349:9063, 1997, 1436–42.
World Health Organization, Disability-adjusted life years (DALYs)
On 13 April 2021, at a two-day meeting attended virtually by 40 000 people, including researchers, business leaders and various civil society groups, African heads of state pledged to increase the share of vaccines manufactured in Africa from 1% to 60% by 2040.
Donors and sponsors
Reuse our work
- All visualizations, data, and text produced by African Futures are completely open access under the Creative Commons BY license. You have the permission to use, distribute, and reproduce these in any medium, provided the source and authors are credited.
- The data produced by third parties and made available by African Futures is subject to the license terms from the original third-party authors. We will always indicate the original source of the data in our documentation, so you should always check the license of any such third-party data before use and redistribution.
- All of our charts can be embedded in any site.
Cite this research
Jakkie Cilliers (2022) Health and WaSH. Published online at futures.issafrica.org. Retrieved from https://futures.issafrica.org/thematic/05-health-and-wash/ [Online Resource] Updated 24 August 2022.