Disease Burden and Mortality

Abstract

In the past years, infectious diseases have been major concern in Africa. However the attention now is slowly shifting toward non-communicable diseases (NCDs), which are on the rise in many parts of Africa due to pollution, Westernized diets, reduced physical activity levels, urbanization, and increased tobacco and alcohol consumption, to name a few. These increases are expected as a country develops. This chapter reviews the change in the death rate, incident rate, and prevalence in the past decade in both infectious disease and NCDs, as well as the key factors that possess an impact on the disease burden.

Africa carries over 20% of the global burden of disease. A lack of local academic research and resources along with recurring natural disasters, military conflicts, and poor economic performance creates unique and formidable challenges for Africa’s healthcare systems. The disease burden in Africa accounted for the loss of 629,603,271 disability-adjusted life years in 2015. This number represents about US$243 billion in income loss, of which 59.1% (US$144 billion) was from communicable, maternal, perinatal, and nutritional conditions; 30.7% (US$74.6 billion) from non-communicable diseases (NCDs); and 10.2% (US$24.8 billion) from injuries. The structure of Africa’s disease burden also has changed in recent years. In the past two decades, incidences of infectious diseases have been overtaken by NCDs as urbanization and Westernization spread across the continent.

This section focuses on changes in the incidence and death rate of selected infectious diseases and NCDs over the past decade, as well as risk factors proved to be correlated with such changes. Though not included in this report, a statistical model and analysis will be run using the factors and data collected in this section. Ideally, understanding the correlations between risk factors, incidence, and death rates of these diseases should provide a reliable prediction of the future disease burden in Africa.

3.1 Infectious Diseases

The three most prevalent infectious diseases in Africa are malaria, HIV/AIDS, and tuberculosis. This section assesses the incidence and death rate of each, as well as relevant policies and treatments.

3.1.1 Malaria

According to the World Malaria Report 2020, an estimated 229 million cases of malaria occurred globally in 2019. About 94% (215 million) of these cases occurred in Africa (27% in Nigeria, 12% in Congo, 5% in Uganda, 4% in Mozambique, and 3% in Niger). However, the overall trend for malaria incidence cases per 1,000 people in Africa declined from 363 in 2010 to 225 in 2019. Among those exposed to malaria, 12 million were pregnant women in 33 moderate-to-high transmission countries in Africa (40% in central Africa, 39% in western Africa, and 24% in eastern and southern Africa). Malaria infection during pregnancy can cause low birth weight.

Figure 3.1 shows the incidence of malaria in five of the eight studied countries, and Fig. 3.2 shows the mortality rates. Malaria is fully eliminated in Algeria, Morocco, and Tunisia, so these three countries are excluded from this section.

Fig. 3.1

Incidence of malaria in five of the studied countries, per 1,000 population at risk. (Data source World Bank. Graph source the author)

Fig. 3.2

Estimated deaths from malaria in five of the studied countries, 2010–2017. (Data source World Bank. Graph source the author)

Understanding the factors behind the eradication in these three countries is essential to address the malaria situation in the remaining five countries. Algeria reported its last indigenous case in 2010 after a successful eradication led by well-trained healthcare workers who responded quickly to new cases, provided free diagnosis and treatment, and applied indoor residual insecticide spray in homes.¹ Morocco was certified malaria-free by WHO in 2010.² It achieved this goal mainly by following WHO guidelines, including surveillance of malariogenic risk factors.³ Reducing malaria requires daily sanitation and rapid diagnosis and treatment. However, the financial burden to achieve the goal can be a hardship. For example, the 2012 budget of the National Malaria Control Programme in Tunisia was US$145,500. Tunisia finally eliminated malaria in 1979 after first implementing controls in 1935. From 1935–1967, its control measures included active case detection, treatment, quarantine, seasonal chemoprophylaxis with quinine, larval control, sanitation, and drainage, which reduced monthly mortality from five to two cases per 1,000 inhabitants (incidence reverted back to five cases during the Second World War). From 1967–1979, malaria was successfully eradicated via indoor residual spraying, intensive active case detection by health workers, efficient laboratory diagnosis, regular reporting, publication, and notification of malaria cases, and radical treatment. Since 1980, Tunisia has focused more on controlling the importation of plasmodium species (the type of mosquito that causes malaria) by monitoring and managing travelers and foreign students.⁴

Though malaria deaths in Africa have dropped by nearly 30% from 533,000 in 2010 to 384,000 in 2019 (about 10 per 100,000 at risk), most (94%) of the world's malaria deaths (409,000 cases globally in 2019) occur in Africa (23% in Nigeria, 11% in the Democratic Republic of the Congo, 5% in the United Republic of Tanzania, and 4% in Niger, Mozambique, and Burkina Faso combined). Out of all malaria deaths among children under five, 84% in 2000 and 67% in 2019 were in Africa.⁵

In Côte d’Ivoire, the incidence of malaria in the general population skyrocketed 21% from 189.9% in 2018 to 229.8% in 2019. At the national level, 15 out of 20 health regions have an incidence rate above the national value (229.8%), as shown in Fig. 3.3.

Fig. 3.3

Incidence of malaria in Côte d’Ivoire, by region and population, 2019. (Data source World Bank. Map and graph source the author)

Over the past decade, Ghana has witnessed an overall decrease in the incidence of 5.61% annually from over 320 cases per 100,000 people in 2008 to 224.3 cases per 100,000. The recently adopted 2015–2020 Ghana Malaria Strategic Plan aims to reduce the malaria burden by 75%. The number of deaths from malaria in Ghana has steadily declined, but deaths remain most prevalent among children under age five.

In Kenya, about 3.5 million new clinical malaria cases and 10,700 deaths occur each year. Malaria cases in Kenya fell gradually from 166.2 cases per 100,000 people in 2004 to 70.1 cases per 100,000 people in 2018. Western Kenya has the highest risk of malaria. Moreover, patients often seek treatment in the private sector, self-medicate, or forego treatment, which can lead to over-diagnosis or uncontrolled laboratory cases (Fig. 3.4).

Fig. 3.4

Malaria in Kenya

In Nigeria, malaria poses a risk for 97% of its population. Case numbers plateaued at 292–296 per 1,000 inhabitants at risk between 2015 and 2018, but 76% of Nigerian live in high-transmission areas. The burden of malaria is three times greater among rural dwellers in comparison to urban dwellers. According to the 2015 Malaria Indicator Survey, malaria prevalence among children under five years of age was 27% (Fig. 3.5).

Fig. 3.5

Malaria admissions and deaths in Nigeria, 2005–2017

In South Africa, malaria cases mainly occur in three provinces: Limpopo, Mpumalanga, and KwaZulu-Natal, due to their low altitudes and the bordering regions of Zimbabwe and Mozambique (Fig. 3.6).

Fig. 3.6

Malaria incidence rates along the elimination continuum, 2018

During 2008–2018, malaria deaths showed a cumulative percentage change of 5.77%, which increases and decreases throughout the decade (Fig. 3.7).

Fig. 3.7

Percentage change in deaths caused by malaria, 2008–2018

Insecticide-treated bed nets (ITNs) effectively reduce parasite prevalence and malaria mortality and morbidity in children under five and pregnant women.⁶ WHO considers ITNs a major, inexpensive malaria prevention method. In 2019, the total funding for malaria control and elimination was estimated at US$3 billion, about 31% of which was contributed by governments in malaria-endemic countries. Of the US$3 billion invested in 2019, 73% (US$2.19 billion) benefited the WHO African Region. As a result, about 213 million ITNs were delivered to malaria-endemic countries in sub-Saharan Africa (64.4 million to Nigeria, 49 million to the Democratic Republic of the Congo, 26.1 million to Ethiopia, 10.4 million to Mali, and 10.2 million to Mozambique). In 2019, about 68% of households in sub-Saharan Africa had at least one ITN, an astounding increase from 5% in 2000, which means 52% of the population has access to an ITN.

Ghana implemented mass ITN distribution in 2006–2008, 2011–2012, 2014–2015, and 2018, resulting in increases in both the proportion of households with access to an ITN and the percentage who slept under an ITN. The percentages of children under five and pregnant women aged 15–49 who slept under an ITN also have steadily increased. The Government of Kenya received support from USAID to procure and distribute ITNs through mass campaigns and at antenatal and child welfare clinics. During 2020–2021, Kenya conducted a mass distribution aimed at universal coverage, defined as one net for every two people in malaria-endemic and endemic-prone counties.

3.1.2 HIV/AIDS

The HIV epidemic is disproportionately concentrated in Africa. In 2018, approximately 37.9 million people were living with HIV, 25.7 million (68%) of whom lived in Africa. Africa further accounted for 1.1 out of 1.7 million newly infected people in 2018. In 2019, 20.7 million people were living with AIDS in eastern and southern Africa, 4.9 million in western and central Africa, and 0.24 million in northern Africa and the Middle East. The adult prevalence was 6.7% in eastern and southern Africa, 1.4% in western and central Africa, and less than 0.1% in northern Africa and the Middle East. There were 730,000 new infections and 30,000 HIV-related deaths in eastern and southern Africa, 24,000 new infections and 140,000 deaths in western and central Africa, and 20,000 new infections and 8,000 deaths in northern Africa and the Middle East.⁷

As the heatmap figures demonstrate, southern and eastern Africa are most affected by HIV. Western and central Africa have comparatively low incidence rates and prevalence but higher death rates. This difference may indicate poor treatment of HIV, despite effective control of the disease. Northern Africa (and the Middle East) generally have lower HIV rates, possibly due to religious rules against premarital sex.

According to the 2020 AIDS Data Book published by UNAID, key populations vulnerable to HIV include men who have sex with men, people in closed settings (e.g. prison), sex workers and their clients, transgender people, and people who inject drugs. In 2019 in western and central Africa, these populations accounted for 69% of new infections (27% in clients of sex workers, 21% in men who have sex with men, and 19% in sex workers). Overall, 60% of the newly infected were female. In eastern and southern Africa, only 28% of cases occurred in the key populations (15% in clients of sex workers, 6% in men who have sex with men, and 5% in sex workers) and again, 60% of the newly infected were female. In both regions, people who inject drugs accounted for only 2% of newly infected cases, and females in general have higher HIV incidence rates.

Northern Africa is a unique case in the region. Data from this region are gathered collectively with the Middle East region and thus may not be of representative northern Africa alone. Religious prohibition on premarital sex also may explain the significantly lower infection rate in the general population. However, the distribution of infections in key populations reveals important information. For example, same-sex relationships are outlawed in this region, yet the percentage of new infections due to sex between men is 23%. The percentage of people who inject drugs is a surprising 43%, even though drugs such as marijuana are illegal in northern African and Middle Eastern countries (Fig. 3.8).

Fig. 3.8

HIV infections in Africa. (Data source UNAIDS DATA 2020. Map source UNAIDS DATA 2020)

In eastern and southern Africa, 87% of people living with HIV know their status (with no significant gender difference), 72% are on treatment, and 65% are virally suppressed. Women tend to have a higher prevalence than men and are slightly more active in receiving ART than men, yet slightly more men are virally suppressed. The gender difference in AIDS-related deaths is also small. However, considering the difference in the number of women and men living with HIV, a bigger portion of infected men have lost their lives to AIDS than women (Fig. 3.9).

Fig. 3.9

Gender differences in HIV status among adults in eastern and southern Africa, 2019. (Data source UNAIDS DATA 2020. Map source UNAIDS DATA 2020)

In western and central Africa, 68% of people living with HIV know their status, 58% are on treatment, and 45% are virally suppressed (Fig. 3.10).

Fig. 3.10

Prevalence (left), incidence (middle) and number of death (right) of HIV. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

Among the eight countries studied in this report, South Africa has the highest HIV burden based on incidence, prevalence, and death rates. Most countries show a downward trend in all three indicators; in South Africa, despite a significant decrease in the death rate, the prevalence of HIV has increased. Nigeria also shows an increase in HIV prevalence, along with a slightly increased death rate (Fig. 3.11).

Fig. 3.11

Knowledge of status, treatment, and viral suppression, 2019. (Data source UNAIDS DATA 2020. Map source: UNAIDS DATA 2020)

In 2019, more than 90% of people living with HIV knew their status in Kenya and South Africa, compared to about 70% in Côte d’Ivoire, Nigeria, Algeria, and Morocco, about 50% in Ghana, and only 20% in Tunisia. Among those who knew their HIV status, 98% were on treatment in Tunisia, followed by more than 80% in Kenya, Côte d’Ivoire, Nigeria, and Algeria, more than 70% in South Africa and Ghana, and only 64% in Morocco. These data indicate that fewer people know their HIV status in Côte d’Ivoire, Ghana, Nigeria, Algeria, and especially Tunisia, where HIV treatment is encouraged and covered. Countries like Morocco and South Africa have high acknowledgement of the disease, but treatment coverage may be a concern. Among those who knew their status and were receiving treatment, more than 90% were virally suppressed in Morocco, Kenya, and South Africa, and more than 70% were virally suppressed in Algeria and Côte d’Ivoire, indicating the effectiveness of HIV treatment. However, a large percentage of people who were virally suppressed did not necessarily receive treatment, which can make it difficult to accurately assess the effectiveness of HIV treatment. Therefore, further research could be done in this area.

In Kenya, 1.4 million people aged 15 and over are living with HIV (0.88 million females and 0.51 million males), and 0.11 million children aged 0 to 14 are living with HIV. Prevalence is 5.8 among women and girls aged 15–49, 3.2 among men and boys aged 15–49, 2.4 among girls up to age 15, and 1.3 among boys up to age 15. Among 35,000 newly infected people aged 15 and over, 22,000 were female. In 2018, the number of people living with HIV reached 1.6 million, making Kenya the third-largest HIV epidemic in the world (alongside Tanzania). In the same year, 25,000 people died from AIDS-related illnesses, a steady decline from 64,000 in 2010. Kenya’s HIV epidemic is driven by sexual transmission and affects all populations and genders, including children, young people, and adults. As of 2015, 660,000 children were orphaned by AIDS. A disproportionate number of new infections in Kenya occur among key populations. In 2014, about 30% of new HIV infections were among these populations.

South Africa has made serious efforts to prevent, treat, and control HIV, as it is the second-leading underlying natural cause of death for males. During 2008–2017, deaths caused by HIV increased by 3.53% (Statistics South Africa 2017), as shown in Figs. 3.12 and 3.13.

Fig. 3.12

Percentage of deaths caused by HIV, 2008–2017. (Data source World Bank. Graph source The author)

Fig. 3.13

Total number of deaths estimated over time versus AIDS-related deaths, 2002–2020. (Data source Department of Statistics South Africa. Graph source Department of Statistics South Africa)

3.1.2.1 ART Treatment

Antiretroviral therapy (ART) treatment is the main treatment to control HIV. This combination of daily HIV antiretrovirals (ARVs) does not cure HIV but helps those living with HIV to live longer. Measuring the coverage of ARV treatment in one country provides insights into the status of the disease and associated death rates. Some of the studied countries provide free ARV treatment to citizens. This report studies the coverage rate of ARV and costs incurred by the patients and the government. For example, in Nigeria, the average unit cost for ARV was US$157 ($1 = NGN363) in 2018, and 65% of people with HIV received treatment in 2019. In Kenya, the average unit cost of one year of adult ART is Ksh 12,032.4 (US$ 115.7). The unit costs vary by regimen type: an adult first-line regimen is Ksh 9,501.44 (US$91.4) per year, a second-line adult regimen is Ksh 26,499.20 (US$254.8) per year, and a pediatric ARV regimen is 17,800.64 (US$171.2) per year.

Under the National AIDS & STI Control Program, the estimated cost of implementing the new guidelines was Ksh 53.4 billion (US$513 million) in FY 2019/20, up from Ksh 47.2 billion (US$ 454 million) in FY 2016/17 (Table 1). Under this scenario, coverage of people living with HIV grew from 80% in 2016 to 95% in 2019, with a projected 5% increase each year.

The Government of Ghana has a current HIV testing target of 100% of all pregnant women. About 1.2 million pregnancies occur per year in Ghana, which accounts for a large percentage (39–44%) of HIV tests. The government aims to provide ARV therapy to all pregnant women who test positive, and all infants born to HIV-positive women will receive two early infant diagnosis tests with baseline yields at 9.7%. The revised ART targets based on the Ghana Health Service/National AIDS Control Programme’s 90–90-90 roadmap (Fig. 3.14) were entered into the 2016 Spectrum AIDS Impact Model for Ghana.

Fig. 3.14

Oadmap 90–90-90 roadmap ART enrollment targets for people living with HIV, by subcategory. (Data source Ghana Health Service/National AIDS control Programme. Table source: Ghana Health Service/National AIDS control Programme)

The average annual unit cost is US$128 for adult first-line ART and US$1,021 for second-line ART. Laboratory fees for patients on ART are US$58 (Figs. 3.15 and 3.16).

Fig. 3.15

HIV service costs per person per year. (Data source Ghana Health Service/National AIDS control Programme. Table source Ghana Health Service/National AIDS control Programme)

Fig. 3.16

HIV treatment monthly costs per month per person (exchange rate for May 3, 2021). (Data source UNAIDS AND MÉDECINS SANS FRONTIÈRES. Table source Funani Mpande)

In South Africa, the provincial government and Médecins Sans Frontières in the Cape Town township of Khayelitsha formed a partnership in 2001 to provide ART district-wide. When the program launched in April 2004, 2,327 patients received treatment. By the end of March 2006, 16,324 had received treatment, mostly limited to a small population in Khayelitsha. Therapy outcomes were reported up to four years after treatment initiation and indicated a peak in AIDS in South Africa in 2006 (demonstrating the large scale of the ART program). Since the national roll-out in April 2004, treatment has been available at public health facilities in every district. In July 2019, a new class of antiretrovirals called integrase inhibitors (e.g. dolutegravir, lamivudine, and tenofovir) was introduced. Integrase inhibitors suppress HIV quickly and effectively with fewer side effects.

3.1.2.2 Discrimination Related to HIV

The stigma, discrimination, and violence toward HIV patients is a key factor that decreases treatment compliance, especially in western and central Africa, where 51.6% of people aged 15–49 will not buy vegetables from HIV-infected shopkeepers, compared to 32.2% in eastern and southern Africa (Fig. 3.17).

Fig. 3.17

Percentage of people aged 15–49 years in eastern and southern (left), and western and central (right) Africa who would not purchase vegetables from a shopkeeper living with HIV, 2014–2019. (Data source UNAIDS DATA 2020. Map source UNAIDS DATA 2020)

According to Kenya’s Act No. 14 law of 2006, parliament must provide measures for the prevention, management, and control of HIV and AIDS and promote public health via appropriate treatment, counseling, support, and care of persons infected or at risk of HIV and AIDS infection. Yet, laws in Kenya and Côte d'Ivoire criminalize the transmission of, nondisclosure of, or exposure to HIV transmission. Kenya and Tunisia criminalize same-gender sexual acts with imprisonment of up to 14 years. Tunisia also criminalizes transgender people; prohibits the entry, stay, and residence of people living with HIV; and requires HIV testing or disclosure for some permits. Kenya and Tunisia require parental consent for adolescents under 18 to access HIV testing. In Côte d'Ivoire, that age limit is 16.

3.1.3 Tuberculosis

Tuberculosis (TB) mainly occurs in Asia and Africa. In 2016, 2.5 million people were affected by TB in Africa, which is 25% of new cases worldwide. Nigeria, South Africa, China, India, Indonesia, and Pakistan account for 60% of TB cases worldwide. TB was the leading underlying cause of death from 2008–2017 in South Africa, especially among males, though the death rate has since declined by about 10.65% (Statistics South Africa 2017). In 2018, TB deaths in Nigeria reached 115,420 or 5.95% of total deaths, with an age-adjusted death rate of 128.71 per 100,000 people. Globally, TB incidence is declining by roughly 2% per year (Fig. 3.18). However, it remains a leading cause of death worldwide, ranking above HIV/AIDS.

Fig. 3.18

Prevalence (left), incidence (middle) and number of death (right) of TB. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

According to WHO, people living with HIV are 20 to 30 times more likely to develop TB than those who do not have HIV. In 2016, 34% of people living with HIV in Africa also had TB.

3.2 Non-communicable Diseases

In addition to infectious diseases, which continue to be a severe issue in sub-Saharan Africa, there has been an increase in the prevalence of non-communicable diseases (NCDs) over the past two decades. NCDs are diseases that are not directly transmissible between humans, such as coronary, oncological, diabetic, and respiratory diseases. Many of these NCDs are due to cardiovascular risk factors, such as unhealthy diets, reduced physical activity, and air pollution (Bigna 2019). WHO predicts that NCDs will be the leading cause of death in sub-Saharan Africa by 2030 (Fig. 3.19).

Fig. 3.19

Non-communicable diseases in five African countries. (Data source World Health Organization. Graph source World Health Organization)

In 2018, WHO published a set of country profiles regarding NCDs. Sub-Saharan countries (Kenya, Ghana, South Africa, Nigeria, and Côte d’Ivoire) showed an average 20.2% increase in NCD-related mortality between 2010 and 2016. South Africa had the fastest increase (76%), followed by Côte d’Ivoire (12%), Ghana (10%), and Nigeria (7%). Kenya showed a 4% decrease in NCDs. In northern Africa, NCDs increased about 15.7% on average, including 21% in Algeria, 19% in Tunisia, and 7% in Morocco. In 2010, NCD rates in northern African countries (about 70%) were higher than in sub-Saharan countries (31%).

This report investigates several predominant NCDs, including cardiovascular, respiratory disorders, cancer, diabetes, stroke, asthma, hypertension, chronic hepatic diseases, and chronic renal diseases. For diseases with various subtypes, such as cancer, the specific type investigated depends on each country’s situation. Overall, this section focuses on the most concerning NCDs of each country (Fig. 3.20).

Fig. 3.20

Prevalence (left), incidence (middle) and number of death (right) of non-communicable disease. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

In Kenya during 2000–2017, deaths due to NCDs (mainly cardiovascular diseases, cancer, and digestive diseases) increased by 72% (Fig. 3.21).

Fig. 3.21

Number of deaths per 1,000, by disease. (Data source World Health Organization. Graph source World Health Organization)

Kenya’s National Strategy for the Prevention and Control of Non-communicable Diseases 2015–2020 indicates that 26% of Kenyan men smoke tobacco and more than 25% of children are exposed to second-hand tobacco smoke at home. Prevalence of insufficient physical activity for adults aged 18 and over was estimated to be 10% for men and 14% for women in 2010. Around 30% of Kenyan adults are overweight, and around 9% are obese. The total annual estimated consumption of pure alcohol in Kenya is 4.3 L per person aged 15 years and older.

In Nigeria during 2009–2019, six non-communicable diseases were the top causes of deaths: ischemic heart disease, stroke, congenital defects, cirrhosis, diabetes, and chronic kidney disease (Fig. 3.22).

Fig. 3.22

Comparison of causes of deaths in Nigeria, 2009 versus 2019. (Data source World Health Organization. Graph source World Health Organization)

In South Africa during 2008–2017, deaths caused by NCDs increased by 14%. Overall mortality cause is categorized as natural and non-natural. Natural causes (e.g. circulatory system and respiratory diseases) account for 88% of deaths. The leading underlying NCD causes of death in 2017 were diabetes mellitus (mostly among women), cerebrovascular diseases, and other heart diseases (Fig. 3.23).

Fig. 3.23

Causes of death in South Africa, 2017. (Data source World Health Organization. Graph source Funani Mpande)

In Tunisia in 2018, NCDs (mainly cardiovascular) accounted for 86% of total deaths. Between 2009 and 2019, the top three causes of deaths were cardiovascular disease, cancer, and diabetes or chronic kidney disease (Figs. 3.24 and 3.25).

Fig. 3.24

Comparison of causes of deaths in Tunisia, 2009 versus 2019. (Data source World Health Organization. Graph source World Health Organization)

Fig. 3.25

Total mortality in Tunisia. (Data source World Health Organization. Graph source World Health Organization)

3.2.1 Cardiovascular Disease

Cardiovascular disease is the leading cause of death globally. Over three-quarters of cardiovascular disease deaths occur in low- and middle-income countries, where people often do not have access to an integrated primary and preventive healthcare system. Without adequate treatment, patients have less access to effective and equitable healthcare, and they often lack the financial capacity to support health spending and out-of-pocket expenditure. The cardiovascular disease thus is often detected at later stages, causing many patients to die younger than they would from other NCDs (Fig. 3.26). The high financial expenditure and death rate also causes heavy burdens for families and governments.

Fig. 3.26

Prevalence (left), incidence (middle) and number of death (right) of cardiovascular disease. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

According to WHO data published in 2018, coronary heart disease deaths in Nigeria reached 108,578, or 5.60%, of total deaths. The age-adjusted death rate is 197.37 per 100,000 of population, ranking Nigeria as 31^st in the world for such deaths, compared to Tunisia, which reached 20,968, or 31.65%, of total deaths for an age-adjusted death rate of 182.62 per 100,000 of the population (ranking 40th in the world). Other forms of heart disease (e.g. cardiac arrest and heart failure) are the 4th-leading cause of underlying deaths in 2017 (Statistics South Africa 2017), though rates decreased by 1.78% from 2008–2017.

3.2.1.1 Ischemic Heart Disease

Ischemic heart disease is a subtype of cardiovascular disease that was previously considered rare in sub-Saharan Africa, but ranked eighth among the leading causes of death in 2008 and first in Algeria and Nigeria in 2009 and 2019 (Fig. 3.27).

Fig. 3.27

Prevalence (left), incidence (middle) and number of death (right) of ischemic heart disease. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

In South Africa, ischemic heart disease was the ninth leading cause of death in 2017 (Statistics South Africa 2017), increasing by about 0.68% from 2008 to 2017.

3.2.1.2 Hypertensive Heart Disease

Hypertension (blood pressure ≥ 140 mmHg) is a risk factor for cardiovascular disease and stroke. Globally, an estimated 1.13 billion people have hypertension, two-thirds of whom live in low- and middle-income countries. Africa has the highest prevalence of hypertension (27%). Reducing tobacco and alcohol consumption, increasing physical activity, and consuming a low-fat, low-salt diet can help prevent and control hypertension. Hypertension-related diseases from 2008 to 2017 by 3.3% (Statistics South Africa 2017). See Fig. 3.28.

Fig. 3.28

Prevalence (left) and number of death (right) of hypertensive heart disease. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.1.3 Stroke

Strokes occur when the blood supply to the brain is interrupted or reduced. A study by Sarfo et al. states that sub-Saharan Africa bears the highest burden of stroke, with an incidence rate of 316 per 100,000, a prevalence rate of 0.14%, and a 1-month fatality rate of 40% (Fig. 3.29).

Fig. 3.29

Prevalence (left), incidence (middle) and number of death (right) of stroke. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

According to the Heart and Stroke Foundation of South Africa, strokes are a leading cause of death in the country, though rates declined by 0.92% from 2008 to 2017 (Statistics South Africa 2017).

3.2.2 Respiratory Disorders

Chronic obstructive pulmonary disease was the fourth leading cause of death in 2005, and by 2025 it is predicted to become the third, surpassing AIDS/HIV in Africa. Risk factors include smoking, air pollution, occupational exposure, and tuberculosis, all challenges for urbanizing African countries. Chronic lower respiratory diseases (e.g. bronchitis) were ranked as the eighth leading underlying natural causes of death in 2017 (Statistics South Africa 2017), though the rate declined by 0.89% from 2008 to 2017 (Fig. 3.30).

Fig. 3.30

Prevalence (left), incidence (middle) and number of death (right) of chronic respiratory diseases. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

Asthma rates have significantly increased due to rapid urbanization. Both incidence and prevalence rates are increasing in most African countries, especially the eight sampled in this study. Death rates are declining or stabilizing, however. In South Africa, asthma rates drastically declined by 6.77% from 2008 to 2017 (Statistics South Africa 2017), though according to the South African Medical Journal, asthma continues to be a burden to children in both rural and urban populations (2018).⁸ Children in urban areas experience severe symptoms, and most lack formal diagnoses and access to treatment (Fig. 3.31).

Fig. 3.31

Prevalence (left), incidence (middle) and number of death (right) of asthma. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.3 Cancer

Cancer has been a low priority in African countries due to the heavy burden of communicable diseases. As of 2006, few facilities were available to provide treatment for cancer.⁹ Cancer incidence, prevalence, and death rates are rapidly increasing in our sample countries, implying that cancer may be the next main focus of Africa’s public health system (Fig. 3.32). Increases in tobacco and alcohol consumption, as well as HIV-related immunosuppression, are key risk factors for cancer.

Fig. 3.32

Prevalence (left), incidence (middle) and number of death (right) of cancers. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.3.1 Breast Cancer

Breast cancer represents the most (27.7%) cancer cases in African countries and is the leading cause of cancer-related death in women according to the Cancer Association of South Africa. Incidence increased by more than 23% between 2012 and 2018 from 1.7 million to 2.1 million (Ferlay et al. 2018).¹⁰ From 2008 to 2019, breast cancer rates increased 3.6% (Statistics South Africa 2017). See Fig. 3.33.

Fig. 3.33

Prevalence (left), incidence (middle) and number of death (right) of breast cancer. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

The five-year survival rate is less than 40% due to financial barriers to mammography screening and a lack of well-trained radiologists and technicians. Most countries in sub-Saharan Africa do not have mammography, and if they do, it is mainly available only in urban areas. Furthermore, the peak age of incidence in breast cancer is lower in sub-Saharan Africa, compared to other regions, which means later diagnoses. Many women are already at an advanced stage when the cancer is detected.

3.2.3.2 Lung Cancer

Lung cancer is the fifth-leading cause of cancer deaths for women and third for men, according to the Cancer Association of South Africa. From 2008 to 2017, lung cancer increased by 2.97% (Statistics South Africa 2017). Prevalence is related to HIV, tobacco consumption, poor economic circumstances, low standard of living, inaccessible and inadequate medical care, urbanization, and air pollution (Fig. 3.34).

Fig. 3.34

Prevalence (left), incidence (middle) and number of death (right) of tracheal, bronchus, and lung cancer. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.3.3 Cervical Cancer

Cervical cancer represents 19.6% of total cancer cases in African countries. It is the second-leading cause of cancer-related deaths in women according to the Cancer Association of South Africa. From 2008 to 2017, deaths caused by cervical cancer increased by 5.3% (Statistics South Africa 2017). See Fig. 3.35.

Fig. 3.35

Prevalence (left), incidence (middle) and number of death (right) of cervical cancer. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

Human papillomavirus (HPV) and lack of HPV vaccines are the most common factors responsible for cervical cancer in Africa. HPV infection usually resolves in immunocompetent women, but it increases their risk of developing cervical cancer. Nevertheless, two-thirds of cervical cancer cases caused by HIV and HPV could be prevented by HPV vaccination. However lack of knowledge about cervical cancer and HPV and a lack of screening centers contribute to the late diagnoses and poor survival rates.

3.2.3.4 Colorectal Cancer

Colorectal cancer is the second-most common cancer among men and third-most common among women, according to the Cancer Association of South Africa. From 2008 to 2017, colorectal cancer deaths increased by 1.73% (Statistics South Africa 2017). See Figs. 3.36.

Fig. 3.36

Prevalence (left), incidence (middle) and number of death (right) of colorectal cancers. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.3.5 Prostate Cancer

Prostate cancer represents 18.1% of total cancer cases in African countries, and it is the leading cause of cancer-related deaths in men. From 2008 to 2017, deaths caused by prostate cancer increased by 4.78% (Statistics South Africa 2017).¹¹ See Fig. 3.37.

Fig. 3.37

Prevalence (left), incidence (middle) and number of death (right) of prostate cancer. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

Race plays an important role in the incidence of prostate cancer. Around 30–43% of black men develop preclinical prostate cancer by the age of 85 years, which is 28–56% higher than in non-black populations. Just like other types of cancers, the lack of screening (such as prostate-specific antigen testing and transrectal ultrasound biopsy), lack of access to healthcare, genetics, lifestyle, and environmental factors result in late diagnoses and low survival rates.

3.2.3.6 Liver Cancer

Liver cancer is the third-leading cause of cancer-related deaths in Africa. Apart from the challenges mentioned previously, such as lack of screening and lack of knowledge, the absence of comprehensive surveillance programs for liver cancer, inaccessible expert medical care, and socioeconomic and sociocultural factors that affect treatment decision-making also make this type of cancer difficult to control (Fig. 3.38).

Fig. 3.38

Prevalence (left), incidence (middle) and number of death (right) of liver cancer. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.4 Diabetes

Diabetes is a key risk factor for developing cardiovascular diseases. In 2019, 19 million adults were living with diabetes in Africa, which is estimated to increase to 47 million by 2045, and 45 million adults have impaired glucose tolerance. Around 60% of adults living with diabetes are undiagnosed. Despite spending US$9.5 billion on diabetes in 2019, rates are still increasing. South Africa has the largest diabetic population, followed by Nigeria. Diabetes mellitus was the second-leading cause of death among men and women and the leading cause of death among women from 2015–2017 in South Africa (Statistics South Africa 2017). Rates have increased by 2.53% from 2008 to 2017. In Kenya, more men than women are affected by diabetes (Fig. 3.39).

Fig. 3.39

Prevalence (left), incidence (middle) and number of death (right) of diabetes. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.2.5 Cirrhosis and Other Liver Diseases

Between 1980 and 2010, cirrhosis-related deaths doubled in sub-Saharan Africa. Chronic alcoholism is the most common cause, followed by lifestyle, sexual partners, and obesity. Nonetheless, from 2008 to 2017, rates of liver disease declined by 4.57% (Statistics South Africa 2017; Fig. 3.40). Currently, the treatment of liver cirrhosis is inaccessible in most of sub-Saharan Africa due to shortages of hepatologists, gastroenterologists, interventional radiologists, hepatobiliary surgeons, and pathologists. Liver transplants are available only in South Africa and considered a rare and expensive treatment that may be further prohibited by the government. Prevention of liver disease requires screening, improved hygiene in health facilities, training or retraining of healthcare workers on safe injection practices, vaccination of hepatitis carriers, reduced alcohol consumption, weight control, and diabetes management.

Fig. 3.40

Prevalence (left) and incidence (right) of cirrhosis and other liver diseases. (Data source Institution for Health Metrics and Evaluation. Graph source The author)

3.3 Substance Consumption

NCDs have many underlying risk factors. Understanding these risk factors can help predict future issues and identify possible treatments. Three main risk factors are covered here: substance consumption (tobacco and alcohol), nutrition, and physical activity. Tobacco causes over 8 million deaths each year, including 1.2 million due to second-hand smoke exposure. Smoking during pregnancy can cause birth defects. Alcohol consumption contributes to 3 million deaths annually and is responsible for 5.1% of the global burden of disease, particularly affecting premature mortality and disability among those aged 15 to 49 years. Both tobacco and alcohol are known risk factors for NCDs, and they are heavily associated with social aspects in many countries. Their harm may be easily overlooked or discounted, and consumers tend to find it challenging to quit.

3.3.1 Tobacco Consumption

In Côte d’Ivoire, where tobacco is the most consumed, men's consumption far exceeds that of women, though it has not increased in recent years (Fig. 3.41).

Fig. 3.41

Tobacco and alcohol consumption. (Data Source World Bank. Graph Source Fofana Daouda)

In Ghana, the 2014 Demographic and Health Survey indicates a 4.8% prevalence of cigarette smoking among males and 0.1% among females. The sale of tobacco products is prohibited for persons under the age of 18. The percentage of people aged 15 years and older who use any tobacco product (smoked or smokeless) on a daily or non-daily basis is 3.1%, which is decreasing and expected to fall further in the next decade. Regional differences in smoking prevalence also exist, with several studies demonstrating higher use among those living in the remote northern areas (31.2% in the northeast, 22.5% in the north, and 7.9% in the northwestern regions). In terms of age groups, 25–34 and 35–59 year-olds have a higher prevalence of cigarette smoking than 15–24 year-olds.

Kenya’s National Strategy for the Prevention and Control of Non-communicable Diseases 2015–2020 indicates that 26% of Kenyan men use tobacco and more than 25% of youth are exposed to second-hand tobacco smoke at home. In 2018, smoking prevalence among adult women was 2.8% and 20.8% among men, both of which decreased from 2005 (Fig. 3.42).

Fig. 3.42

Tobacco smoking prevalence. (Data Source National Strategy for the Prevention and Control of Non-communicable Diseases 2015–2020. Graph Source National Strategy for the Prevention and Control of Non-communicable Diseases 2015–2020)

Nigeria has made considerable progress in controlling tobacco consumption. In 2016, 246 men and 64 women died every week from tobacco consumption, which is low in comparison to other low-Human Development Index countries (Figs. 3.43 and 3.44). Smoking in Nigeria is prohibited in public places. A 2018 report by the United Nations Office on Drug and Crime revealed marijuana to be the most consumed substance in Nigeria (about 10.8% of the population, or 10.6 million Nigerians). Possession of cannabis carries a minimum sentence of 12 years in prison.

Fig. 3.43

Deaths from smoking, 1990–2017. (Data source Institution for Health Metrics and Evaluation. Graph source Our World in Data)

Fig. 3.44

Smoking in Nigeria, 2016. (Data source Institution for Health Metrics and Evaluation. Graph source Ademola Olokun)

In South Africa, tobacco consumption has declined overall but remains more prevalent among males. The overall percentage of smokers exceeded 5% in 2012 and 2016. For women, it drastically declined in 2016, with an overall percentage of less than 2% for all age groups. Between 2008 and 2017, smoking among men decreased by about 3.5% and by 1.6% among women in South Africa (Fig. 3.45).

Fig. 3.45

Prevalence of smoking in South Africa, 2008–2017. (Data Source World Bank. Graph Source Funani Mpande)

From 2012 to 2016, the population of women who smoked cigarettes declined with age, whereas it increased among men (Fig. 3.46).

Fig. 3.46

Percentage of South Africans who smokes cigarettes, 2012 versus 2016. (Data Source World Bank. Graph Source Funani Mpande)

Only pure tobacco was recorded in 2016 (vaping was excluded), and men consumed about three times as many cigarettes as similarly aged women (Fig. 3.47).

Fig. 3.47

Percentage of South Africans who smoked other types of tobacco, 2012 and 2016. (Data Source World Bank. Graph Source Funani Mpande)

After 2010, deaths reported or associated with smoking declined or the cause of death was listed as “unknown or unspecified,” indicating poor reporting on death notification forms (World Bank 2017). See Figs. 3.48 and 3.49.

Fig. 3.48

Percentage of South Africans who smoked any type of tobacco, 2016. (Data Source World Bank. Graph Source Funani Mpande)

Fig. 3.49

Percentage of deaths among people aged 16 and older, by smoking status, 2008–2017. (Data Source World Bank. Graph Source Funani Mpande)

The cigarette tax has increased over the past three years to R2.13 (0.15 US$; 0.12 Euro exchange rates as of May 7, 2021) for a pack of 20 cigarettes and R14.44 (1.02 US$; 0.84 Euro exchange rate) for cigars (Fig. 3.50).

Fig. 3.50

Cigarette taxes, 2019–2021. (Data Source World Bank. Graph Source Funani Mpande)

3.3.2 Alcohol Consumption

Alcohol consumption in Algeria, unlike many other sampled countries, has been decreasing since 1961 (Fig. 3.51).

Fig. 3.51

Alcohol consumption, 1961–2016. (Data Source World Health Organization. Graph Source World Health Organization)

In Nigeria, alcohol per capita consumption increased from 2010 to 2016 by an overall rate of 1.91% (3.21% for men and 0.61% for women). There is no policy on alcohol sales in Nigeria, and age restrictions are not effective, even with a 20% excise duty tax on alcohol. Alcohol is banned in some northern parts of Nigeria due to its Muslim-dominated population (Fig. 3.52).

Fig. 3.52

Alcohol use per capita among those aged 15 and older. (Data Source World Bank. Graph Source Ademola Olokun)

In South Africa, per capita alcohol consumption decreased for all from 2005 to 2016. For men, alcohol consumption decreased by 23.41%, and for women by 21.11%, contributing to an overall reduction of 25.61% (Fig. 3.53). According to the 2016 South Africa Demographic and Health Survey, men in South Africa tend to drink more alcohol than women in every age group. Women tend to be judged or shamed for consuming large volumes of alcohol or drinking in social spaces, for instance. Most beer brands in South Africa are associated with masculinity.

Fig. 3.53

Percentage of men and women who used alcohol in South Africa, 2016. (Data Source World Health Organization. Graph Source Funani Mpande)

From 2010 to 2016, beer consumption increased by 7.9% but decreased by 9.6% for other alcohols (sorghum, millet, maize beers, cider, fortified wine, fermented wheat, rice, and other beverages). Wine and spirit consumption increased slightly by 2%, according to the WHO Global Status Report on Alcohol and Health.

The CAGE questionnaire is used to check whether an individual has an alcohol addiction. More than 20% of men, mainly those aged 20–34, tested high on this questionnaire, compared to less than 4% of women (South Africa Demographic and Health Survey 2016; Figs. 3.54 and 3.55).

Fig. 3.54

CAGE results. (Data Source Department of Statistics South Africa. Graph Source Funani Mpande)

Fig. 3.55

Alcohol use per capita in South Africa for people aged 15 and older, 2005–2016. (Data Source Department of Statistics South Africa. Graph Source Funani Mpande)

Alcohol taxation increases every year, and the most taxed products are spirits and sparkling wine. The spirit increased R8.39 (US$0.60 or 0.49 Euro, exchange rate on May 7, 2021) between 2019 and 2021, and sparkling wine increased R1.14 (US$0.081 or 0.067 Euro). (National Treasury 2021).

Recorded alcohol per capita consumption is the number of liters of alcohol consumed by those aged 15 and older per capita over a calendar year in a country. This indicator accounts for consumption using data from production, import, export, and sales data via taxation (Fig. 3.56).¹²

Fig. 3.56

Alcohol consumption per capita among those aged 15 and older. (Data Source Department of Statistics South Africa. Graph Source Funani Mpande)

3.4 Nutrition

3.4.1 Nutrition

In Ghana, the calorie and protein availability per capita per day has increased since 1984. However, the amount of animal, fish, and seafood protein has not changed much (Fig. 3.57).

Fig. 3.57

Calorie and protein availability per capita in Ghana, 1984–2011. (Data Source International Food Policy Research Institute. Graph Source International Food Policy Research Institute)

According to the Food and Agriculture Organization of the United Nations, the average food intake in Kenya is 2,155 kcal/person/day. Of this, 1,183 (55%) kilocalories come from maize, wheat, beans, potatoes, plantains, and rice. Maize is the most important cereal crop and main staple food, providing more than one-third of the caloric intake, and it accounts for about 56% of cultivated land in Kenya. Most Kenyans prefer white corn flour to produce ugali, a thick porridge of maize meal that is usually eaten daily with vegetables, meat, or fermented milk. On average, a Kenyan consumes 88 kg of maize products per year, followed by wheat (17% of staple food consumption) and beans (9% of food calories and 5% of total food calories in the national diet; Fig. 3.58).

Fig. 3.58

Dietary intake of essential foods and nutrients among Kenyans aged 25 and over. (Data source Global Nutrition Report. Graph source Global Nutrition Report)

Kenya produces potatoes, plantains, and rice but needs to import wheat and more rice due to food shortages. Nevertheless, Kenya is on track to meet four maternal, infant, and young child nutrition targets. Some progress has been made to reduce anemia among women, which affects 27.2% of women aged 15–49. Progress also has been made toward achieving low birthweight targets, as 11.5% of infants are born with a low weight. Kenya has shown limited progress toward NCD targets and no progress toward obesity targets (11.1% of adult women and over 2.8% of adult men are obese). Kenya's obesity prevalence is lower than the regional average of 18.4% for women and 7.8% for men.

According to the UN Food and Agriculture Organization, South Africans have increased their fat intake to 13.93 g/day from 1992 to 2018 and decreased their protein intake by 1.05 g/day. According to Steyn et al. (2006), the South African population is increasingly consuming a typical Western diet with higher calories, saturated fat, animal protein, sodium, and sugar. Fruit and vegetable intake also is low (Fig. 3.59).

Fig. 3.59

Fat and protein intake in South Africa, 1992–2018. (Data Source UN Food and Agriculture Organization. Graph Source Funani Mpande)

3.4.2 Malnutrition

Malnutrition includes undernutrition (wasting, stunting, underweight), inadequate supply of vitamins or minerals, excess weight, and obesity. Malnutrition can result in diet-related NCDs. The body mass index (weight in kilograms divided by the square of height in meters, kg/m²) is a commonly used index to classify weight in adults. According to WHO classifications, for individuals aged 20 and older, a BMI less than 18.5 is considered underweight, 18.5 to 24.9 is normal weight, 25 to 29.9 is overweight, and 30 or more is obese.

3.4.3 Undernutrition

The three sub-forms of undernutrition are wasting (too thin concerning height), stunting (too short concerning age), and underweight. Wasting may be due to food insufficiency or infectious disease (e.g. diarrhea). In 2020, 149 million children under five years old were stunted, 45 million were wasted, and 38.9 million were overweight or obese. Undernutrition is linked to 45% of deaths among these children. Stunting is the moderate and severe percentage of children aged 0–59 months below two standard deviations from the median height for age set by the WHO child growth standards. It may result from chronic or recurrent undernutrition, often linked to poor socioeconomic status, poor maternal health and nutrition, frequent illness, and inappropriate infant and toddler feeding. Underweight is determined if the BMI of a child falls under the fifth percentile compared to other children the same age. Children who are underweight may be stunted, wasted, or both.

In Algeria between 2004 and 2018, the prevalence of undernourishment as a percentage of the population declined at a moderate rate from 7 to 2.8%. The prevalence of underweight children under five was at 2.7% in 2019, down from 3% in 2012 (Fig. 3.60).

Fig. 3.60

Prevalence of undernourishment in Algeria. (Data source Global Nutrition Report. Graph source Global Nutrition Report)

In Côte d’Ivoire, the undernourished population reached almost 20% in 2018, which is slightly higher than in 2016 and lower than in 2014 by just more than 0.4%. Food insecurity due to the inaccessibility and instability of food production is widespread in the country, affecting 12.8% of the population (Fig. 3.61).

Fig. 3.61

Prevalence of undernourishment in Côte d’Ivoire (percentage of population). (Data Source World Bank. Graph Source Fofana Daouda)

Kenya is on track to meet its target for reducing stunting. Its rate is 26.2% of children under age five affected, which is lower than the average of 29.1% across Africa. Kenya also is on track to reducing waste among children under five. Only 4.2% of children are affected, compared to 6.4% in Africa (Fig. 3.62).

Fig. 3.62

Prevalence of undernourishment. (Data source Global Nutrition Report. Graph source Global Nutrition Report)

According to the Global Hunger Index 2020, Nigeria ranks 98th out of 107 countries (the higher the number, the worse the situation). As shown in Fig. 3.63, the prevalence of undernourishment as a percentage of the total population increased from 2010 to 2018. The increase was a direct or underlying cause of 45% of all deaths of children under five. Inequality plays a significant role in these statistics, as the northern region is considerably less wealthy than the southern region. Recent terrorist attacks in some states in the northern region also contribute to this disparity.

Fig. 3.63

Prevalence of undernourishment as a percentage of the population. (Data source Global Hunger Index. Graph source Ademola Olokun)

In South Africa, the estimated stunting proportions declined by 0.9% from 2010 to 2020, according to UNICEF/WHO/World Bank (2017). See Figs. 3.64, 3.65, and 3.66.

Fig. 3.64

Prevalence of wasting in children under five in South Africa. (Data Source World Bank. Graph Source Funani Mpande)

Fig. 3.65

Prevalence of stunting in children under five in South Africa. (Data Source World Bank. Graph Source Funani Mpande)

Fig. 3.66

Stunting proportions in South Africa, 2010–2020. (Data Source UNICEF. Graph Source Funani Mpande)

According to the Global Nutrition Report (2021), both wasting and stunting declined from 2004–2016. Boys tend to have higher occurrences than girls, but wasting among boys declined by 6.9%, compared to 3.9% among girls after a temporary increase in 2012. Stunting declined by 11.5% for boys and 5.3% for girls. The prevalence of underweight adults in South Africa declined from 2007 to 2016 (Fig. 3.67). Males are more likely to be underweight than females: the percentage change for males is 1.8% and 0.6% for females.

Fig. 3.67

Underweight prevalence among adults aged 18 years and older in South Africa. (Data source Global Nutrition Report. Graph source Funani Mpande)

In South Africa, undernutrition most affects young people aged 15 to 24 years. Among underweight South Africans, males have higher BMIs than females (Figs. 3.68 and 3.69). For most age groups, undernutrition has declined marginally with time except among 35–44 year-olds, for whom it increased by 0.001. Underweight men aged 45–54 years increased by 0.019% in 2008, and women aged 55–64 years increased by 0.004 in 2008.

Fig. 3.68

BMI among underweight men. (Data source Global Nutrition Report. Graph source Funani Mpande)

Fig. 3.69

BMI among underweight women. (Data source Global Nutrition Report. Graph source Funani Mpande)

3.5 Urbanization

Urbanization refers to the percentage of a population living in cities. It signifies a demographic transition from an agriculture-based economy to an industrial, technological, and service-based economy. In principle, cities offer more favorable settings for addressing social and environmental problems than rural areas. As such, urbanization can help measure the degree of development of a country, as cities provide better jobs, education opportunities, income, healthcare, and other services. However, it may also imply an increase in office jobs, which requires less physical work and is likely to be a risk factor for weight- and heart-related diseases, such as hypertension and obesity.

The urban population in Algeria has also increased by 6.3% from 2009 to 2019 (Fig. 3.70) A similar trend is observed in Côte d'Ivoire (Fig. 3.71).

Fig. 3.70

Urban population (%). (Data source World Bank. Graph source Abdelkader Bouregag)

Fig. 3.71

Share (%) of urban population in total population. (Data source World Bank. Graph source Fofana Daouda)

The total percentage of South Africans living in urban areas has continuously increased over the past decade by 4.11% from 2011 to 2019 (Fig. 3.72). Urbanization is common in major cities as people migrate for better employment and living conditions.

Fig. 3.72

Percentage of South Africans living in urban areas. (Data source World Bank. Graph source Funani Mpande)

3.6 Physical Activity

Physical activity is a key risk factor for obesity. Decreasing physical activity is observed in many developing countries, mainly due to job structure changes caused by urbanization. A 2018 study by BMC Public Health reported the country-wide prevalence of physical inactivity among adults aged 18–64 years in Kenya and identified the following populations to be targeted for interventions: women, middle-aged people (40–65), middle-class people, and post-secondary students. Physical activity in Kenya is mostly associated with work rather than health. This self-report should be considered with caution, however, as answers might be subjective. Among the four major risk factors for NCDs, physical inactivity is the only one with no associated policy (Figs. 3.73 and 3.74).¹³

Fig. 3.73

Prevalence of insufficient physical activity among adolescents in school-aged 11–17 in Kenya, 2001–2016. (Data source BMC Public Health. Table source BMC Public Health)

Fig. 3.74

Prevalence of insufficient physical activity among adults in Kenya. (Data source BMC Public Health. Table source BMC Public Health)

Culture may contribute to physical activity preferences. For example, in some rural areas in Nigeria and South Africa, people view voluptuousness as a symbol of wealth and health. They believe fat provides resistance to diseases like HIV. Women tend to have lower physical levels, as many work as stay-at-home housewives. South Africa has high levels of physical inactivity, and women tend to be more physically inactive than men across all age groups. School and sports activities provide physical activities for younger populations aged 15–24 (Figs. 3.75 and 3.76).

Fig. 3.75

Percentage of South Africans that were physically inactive in 2003, by gender. (Data source World Bank. Graph source Funani Mpande)

Fig. 3.76

Percentage of South Africans that were physically inactive in 2012, by age. (Data source World Bank. Graph source Funani Mpande)

According to Mlangeni et al. (2018), a 2012 population-based household survey elicited factors that influence physical inactivity in South Africa and found that individuals who reported physical inactivity had higher educations (i.e. higher socioeconomic status), which increased the likelihood of moderate physical activity. Females living in urban areas tend to be moderately more physically active as they age, whereas married females living in rural areas and with poorer self-rated health tend to engage less in physical activity (Figs. 3.77 and 3.78).

Fig. 3.77

Average BMI of men in South Africa. (Data source Global Nutrition Report. Graph source Funani Mpande)

Fig. 3.78

Average BMI of women in South Africa. (Data source Global Nutrition Report. Graph source Funani Mpande)

3.7 Overweight

Excess weight and obesity reflect abnormal or excessive fat accumulation that may impair health. For adults, being overweight is defined as a BMI between 25.0 and 30.0. For children under five, it is a weight-for-height greater than two standard deviations above the WHO Child Growth Standard, or above the 85th percentile in BMI compared to similarly aged children. For children between 5 and 19, overweight is defined by a BMI-for-age greater than one standard deviation above the WHO Growth Reference median. In 2016, more than 1.9 billion adults aged 18+ were overweight.

The prevalence of overweight people in Algeria increased from 47.1% in 1997 to 62% in 2016, growing at an average annual rate of 1.46%. Similar patterns occur in Kenya. The 2008 Kenya Demographic Health Survey finds that 25% of women in Kenya are overweight or obese and in urban areas, such as Nairobi, 41% of women are overweight or obese women. The prevalence of overweight children under five years old is 4.1%. However, Kenya is on track to prevent the figure from increasing (Fig. 3.79).

Fig. 3.79

Prevalence of overweight children under five in Kenya, 2000–2015. (Data source Global Nutrition Report. Graph source Global Nutrition Report)

In South Africa, the BMI index among overweight people is similar for both genders in the urban areas and exceeded 0.2 in both 1998 and 2008 (Fig. 3.80). Males in rural areas tend to have a rate that is below 0.2, whereas females in rural areas have higher BMIs than those in urban areas.

Fig. 3.80

BMI of men and women in South African aged 15 and older, 1998 and 2008. (Data source Global Nutrition Report. Graph source Funani Mpande)

More than 70% of women over 35 years old in South Africa were obese in both 1998 and 2008. Men’s BMI increased by about 5% for each age group from 1998 to 2008 (Fig. 3.81).

Fig. 3.81

Percentages of overweight or obese men and women in South Africa, 1998 and 2008. (Data source Global Nutrition Report. Graph source Funani Mpande)

3.7.1 Obesity

In Algeria, male obesity prevalence in 2016 was 19.9%, and female obesity prevalence was 34.9%. Between 1997 and 2016, it grew substantially among men from 9 to 19.9%, an increasing annual rate that peaked 5.32% in 1999 and then decreased to 3.65% in 2016. Obesity prevalence among women increased from 22.4% in 1997 to 34.9% in 2016, growing at an average annual rate of 2.36%.

In Ghana, the prevalence of obesity among all adults increased between 2009 and 2016. Like all other samples, women tend to have a higher prevalence of obesity than males (Fig. 3.82).

Fig. 3.82

The prevalence of obesity among adults in Ghana. (Data source World Bank. Graph source Gilbert Gadzekpo)

Kenya has shown limited progress toward achieving diet-related NCD targets. The country has shown no progress toward achieving obesity targets, with an estimated 11.1% of women and 2.8% of men aged 18 years and over living with obesity. Kenya's obesity prevalence is lower than the regional average of 18.4% for women and 7.8% for men. At the same time, diabetes is estimated to affect 6.2% of adult women and 5.8% of adult men (Figs. 3.83, 3.84, 3.85, and 3.86).

Fig. 3.83

Prevalence of obesity in adults. (Data source World Bank. Graph source Beatrice Birir)

Fig. 3.84

BMI for those aged 15 and older. (Data source Global Nutrition Report. Graph source Beatrice Birir)

Fig. 3.85

Average BMI for women in South Africa. (Data source Global Nutrition Report. Graph source Funani Mpande)

Fig. 3.86

Average BMI for men in South Africa. (Data source Global Nutrition Report. Graph source Funani Mpande)

In South Africa, obesity is ranked fifth as a risk factor for early death or disability. Urban populations tend to have higher BMIs than rural ones. The BMI rate, measured using the post-stratification weights, exceeded 0.2 for women in 1998 and 2008 in both locations (Figs. 3.85, 3.86, and 3.87).

Fig. 3.87

Prevalence of obesity in children aged 5–19. (Data source World Bank. Graph source Funani Mpande)

3.8 Summary

In the past years, infectious diseases (e.g. HIV, malaria, and TB) have been major concerns in Africa. As a result of financial and medical resources invested in controlling the spread and influence, especially preventive care, death rates from all three studied infectious diseases have either declined or remained low in all samples in the past decade. Education, prompt screening and diagnosis, and affordable, accessible, and effective treatment are key contributors to this success.

Attention now is slowly shifting toward NCDs, which are on the rise in many parts of Africa due to pollution, Westernized diets, reduced physical activity levels, urbanization, and increased tobacco and alcohol consumption, to name a few. These increases are expected as a country develops. However, because Africa has committed most of its health resources to infectious diseases, it has a severe scarcity of resources, staff, and facilities to treat NCDs and related social issues, such as preventative care (e.g. education, screenings), treatment compliance, and social stigma.

Identifying, monitoring, and reducing risk factors can be a cost-effective way to reduce death from NCDs like cardiovascular disease and diabetes. Proper education and advocacy are key elements of this effort. Considering the lack of financial capacity in most African countries, reducing the incidence of NCDs should cost much less than treating them. For example, the government can increase taxes on cigarettes, tobacco, and alcohol to reduce consumption, which is essential to prevent lung and other cancers. Paying attention to NCDs does not mean infectious diseases are no longer the priority, as the two are often interrelated. For example, HIV patients are more vulnerable to cancer. Therefore, maintaining expertise in infectious diseases is still necessary.