Corresponding Author Ole F. Olesen, Health Directorate, Directorate General for Research, European Commission, Rue du Champ de Mars 21, 1050 Brussels, Belgium. Tel.: +32 22 953 999; E-mail: email@example.com
Le profil des maladies en Afrique subsaharienne change et de nombreux pays sont confrontés à une nouvelle et croissante menace par des maladies non transmissibles. La plupart des prédictions du changement du profil des maladies en Afrique subsaharienne ont été jusqu’à présent fondées sur des extrapolations simples de l’histoire des pays industrialisés du Nord. Cette revue présente une vision plus large et décrit comment l’interaction entre les maladies infectieuses et non infectieuses, des facteurs génétiques spécifiques et une distribution déséquilibrée des ressources pour la recherche en santé, peuvent alimenter une nouvelle crise sanitaire non nécessaire dans de grandes parties de l’Afrique. Pour éviter cela, la perception traditionnelle de la santé humaine et le bien-être en Afrique devrait changer drastiquement. Cependant, plus de 90% du financement de la recherche en santé en Afrique subsaharienne reste consacré au VIH/SIDA, au paludisme et à la tuberculose. Qu’est-ce qui n’a pas marché dans l’établissement des priorités et comment pouvons-nous changer cela?
Los patrones de enfermedad en África subsahariana están cambiando y muchos países se están enfrentando a una nueva y creciente amenaza de enfermedades no infecciosas. La mayoría de las predicciones sobre los patrones cambiantes de enfermedad en el África subsahariana se han basado hasta ahora en simples extrapolaciones realizadas a partir del historial de los países industrializados del norte. En esta revisión se presenta una visión más amplia y se describe como la interacción entre las enfermedades infecciosas y las no infecciosas, los factores genéticos específicos y la distribución sesgada de recursos para la investigación en salud pueden exacerbar una nueva, pero innecesaria crisis sanitaria, en grandes partes de África. Para evitarlo, la percepción tradicional africana de la salud y del bienestar humano tendrían que cambiar de forma dramática. Sin embargo, más del 90% de los fondos para la investigación en salud para el África subsahariana continúa estando destinados al VIH/SIDA, la malaria y la tuberculosis. ¿Dónde ha fallado la priorización y como podemos cambiarlo?
The life expectancy in Sub-Saharan Africa (SSA) is 50 years, the same as 20 years ago and the lowest of all regions of the world. The lack of improvement in life expectancy is in stark contrast to the improved economic situation of the African continent. Despite the general view conveyed by most international media, many countries in SSA have experienced a relative economic success in recent years with an average growth in GDP above 5%, while the annual influx of foreign capital as direct investments (FDI) has more than doubled during the last decade (Economist Intelligence Unit 2007). The African economy may even be less affected than other economies by the ongoing financial crisis because of its limited size and lower dependency on export of consumer goods. Unfortunately, this has not translated into an improved health situation for the people in SSA. One of the main reasons is the AIDS epidemic, which affects this region more than any other part of the world. Nearly, one in every five deaths is caused by AIDS, and AIDS causes a staggering 17% of total disability-adjusted life years (DALY) (Mathers & Loncar 2006). The second reason is less obvious, but many countries are now confronted with an emerging wave of chronic diseases. This calls for a new paradigm for health research in Africa and a critical revision of research priorities.
The sixth goal of the Millennium Declaration of 2000 promised ‘to combat HIV/AIDS, malaria and other diseases’. This goal has led to considerable financial mobilisation to ambitious initiatives such as the Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM), the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR), and the European and Developing Countries Clinical Trials Partnership (EDCTP). Activities to combat the so-called other diseases have largely been limited to tuberculosis (TB), and this has created a situation where health and research funding for SSA has practically been monopolised by HIV/AIDS, malaria and TB programmes. The strained healthcare systems in many African countries have therefore been heavily directed towards the detection and treatment of these three diseases, although they account for <25% of the total disease burden in SSA, both in terms of mortality and in terms of DALY (WHO 2008). The disease burden for AIDS, malaria and TB is furthermore predicted to decrease significantly over the next two decades and will, as a group, contribute with <15% of the total disease burden by 2030. A major part of this predicted decline is due to wider availability and access to highly efficient and affordable medication for HIV/AIDS.
Contrary to this, the next 10–20 years will see a dramatic increase in the prevalence of non-communicable diseases (NCD), which will account for 46% of mortality and nearly 40% of disease burden in SSA by 2030 (World Health Organization 2008). This will mainly be driven by steep changes in the prevalence of cancer, cardiovascular diseases and diabetes. The prevalence of both cancer (Ferlay et al. 2010) and diabetes (Mbanya et al. 2010) is thus predicted to double during the next 15–20 years. Total DALY attributed to NCD will soon exceed the combined DALY from AIDS, malaria and TB, and it is even predicted to exceed the total burden of all infectious diseases around 2025. A revision of the approach to research and health care in SSA is therefore urgently needed, but international donors and health communities have generally been slow to respond to the changing environment.
New lifestyle and new risk factors
The economic development in many African countries has triggered a rapid adaptation of western lifestyles with less physical activity, and higher consumption of alcohol, tobacco, fat, sugar and salt. This tendency is particularly pronounced in areas with rapid urbanisation (Vorster et al. 2011). Starvation and malnourishment remain important issues in many places of Africa, but other parts of the continent are paradoxically experiencing a rapidly increasing problem of overweight and associated illnesses. Many countries across Africa have adult populations where the prevalence of diabetes is approaching or exceeding 5% (International Diabetes Federation 2011), higher than in many industrialised countries.
The overall smoking rates in Africa are still relatively low, but embedded poverty potentiates the harmful effect of tobacco on certain diseases, and the impact of smoking in resource poor settings is far more severe than in the industrialised part of the world. The largest risk of smoking in Africa is thus for diseases such as chronic obstructive pulmonary disease (COPD) and TB – all in addition to well-known tobacco-related illnesses such as cancer and ischaemic heart disease.
While Africa is increasingly exposed to risk factors for NCD, the incidence of communicable diseases stays high, as the underlying infectious agents remain in the environment, either as latent infections in large population groups or in animal reservoirs. The clinical burden of infectious diseases will become smaller as they will increasingly be controllable, but medical tools on their own will often be insufficient to eliminate the pathogens. Highly active antiretroviral treatment (HAART) for AIDS and long-term drug treatment for TB may overcome the diseases, but not eliminate the HIV virus or mycobacterium from the body. Similarly, widely used anti-helminthic drugs such as ivermectin do not kill all stages of the invading worms. Without concomitant improvements in housing, nutrition and access to infrastructures such as sanitation and clean water, the vast pool of infectious agents will not become eliminated and could even fuel the growth of NCD. Many infectious agents can cause or propagate severe chronic diseases, ranging from cervical cancer to asthma and depression (Table 1). Nearly 25% of all cancers in developing countries are presumed to be caused by infectious agents (Jones 1999), and the number for SSA could be even higher than this. The two most common male cancers in Africa (Kaposi’s sarcoma and liver cancer), as well as the most common female cancer (cervical cancer), are caused or potentiated by viral infections. Schistosomiasis and loa loa infection may trigger bladder cancer and endomyocardial fibrosis, respectively, while group A β haemolytic streptococcal infections can induce rheumatic heart disease. Little is known about the effect of comorbidity between infectious and non-infectious diseases on a large scale, but the cumulative effects on public health could be significant on both the short and long terms. This scenario becomes relevant when comparing the geographical distributions of risk factors for health in Africa (Figure 1). This reveals that the same populations are often double exposed to pre-existing infectious agents as well as the emerging risk factors for NCD. In some areas of Eastern and Central Africa, there is potentially a significant colocalisation between obesity, HIV and neglected infectious diseases. The same poor populations are therefore often at high risk for both infectious and non-infectious diseases.
Table 1. Infectious agents that are causing or may contribute to non-communicable pathologies in Sub-Saharan Africa
Funding does not match the real disease burden in Africa
African health research is heavily dependent on foreign donors, but allocation of research funding is often designed to serve the goals of donor organisations rather than the long-term goals of recipient countries. The Global Ministerial Forum on Research for Health in Bamako, Mali, in 2008 affirmed the importance of health research for Africa and particularly for research on NCD (Stuckler et al. 2008). However, most donors have maintained control and eradication of infectious diseases as their top priority, often addressing a single or a few high-profile diseases.
Private and public funding for health research in Africa remains therefore disproportionately focused on the three major infectious diseases, whereas only smaller amounts have been allocated to confront other diseases (Moran et al. 2009). This is also reflected in the disbursements from the world’s two major public funders of biomedical research, namely the United States National Institute of Health (NIH) and the European Commission’s Framework Programmes. In the 5-year period from 2007 to 2011, the NIH disbursed, according to the research portfolio online reporting tool (http://report.nih.gov/index.aspx), more than 200 m USD to research groups in SSA, but only about 5% of this funding was specifically targeted towards NCD, and <1% was allocated to NID research activities, whereas the vast majority of funding was earmarked for HIV/AIDS, malaria and TB. The same trend is obvious for the European Commission’s Framework Programmes for Research. During the latest completed Framework Programme (FP6, 2002–2006), approximately 13 m EUR were allocated to health researchers in SSA, but more than 90% was earmarked to research projects related to HIV/AIDS, malaria or TB. Many private foundations and charities have side-lined with the public sector in recent years and provided very generous funding to health research and capacity building in Africa and other developing countries. However, only few initiatives have been launched to tackle NID and even fewer to address chronic diseases. The largest private funder in global health, the Bill and Melinda Gates Foundation, is heavily biased in its funding towards HIV/AIDS, malaria and TB, with relatively little investment in neglected infectious diseases and with no major initiatives in chronic diseases in its research portfolio (McCoy et al. 2009).
With few exceptions, the portfolios of other big international charity donors have followed the same trend. Substantial resources have therefore in many cases been concentrated around a few research teams in the receiving countries. Some of these have subsequently become highly influential in local priority setting, and this can lead to skewed distribution of sparse resources within the African countries. Research funding has thus in many cases been disbursed without a proper analysis of the long-term benefit on public health in Africa. The result is a severe underfunding of research for NID and NCD in SSA in comparison with the actual disease burden, which they represent.
As a consequence, many countries across SSA are now facing a two-sided war against pre-existing infectious diseases and increasing prevalence of chronic diseases. Recent favourable development on this aspect includes the high-level meeting in September 2011 of the United Nations General Assembly on the prevention and control of NCD, which focused international attention on the need for a coordinated, multisectoral response. This followed the establishment by WHO, the World Bank, the World Economic Forum and a range of international NGOs (such as the World Heart Federation, International Diabetes Federation and the International Union against Cancer) of a global network (NCDnet) to promote research and control of NCD at global and national level.
Better knowledge about diseases and how to prevent them means that many health conditions could be improved with relatively small and coordinated investments in the right places, but funding agencies and policy makers are often reluctant to divert scarce resources into new areas. This situation will only change if African governments provide leadership and demand international donors to consolidate their funding priorities rather than competing with each other in isolated silos. To achieve this, African countries must prioritise health and health research on their own political agenda. The African Union (AU) member states pledged in the Abuja declaration of April 2001 to allocate 15% of national budgets to the health sector, but 10 years later, there has been little progress to reach this goal and some countries have actually reduced spending. The development of suitable, balanced and adequate health systems in SSA requires local academic and political leadership. Future health investments should better reflect the true disease burden and try to confront the emerging public health issues before they manifest themselves as serious problems. This is particularly important in setting priorities for research activities, where the time from implementation to delivery is often long.