The database searches returned 2,171 articles, and 340 additional records were identified from hand-searching reference lists, producing a total of 883 (40.67%) unique records screened after removal of duplicates. Overall, 131 (14.83%) were published during 1960 to1990 (30 years) compared to an increase of approximately 6 times, 782 (85.16%) during 1990 to 2011(21 years). Of these, 89 described the trend of malaria events that were included and assessed from SS Africa and P.R. China during 1960–2011. Our findings showed three increasing areas of interest. First, the political and financial commitment and investments through scaling up of malaria intervention coverage programmes: (indoor residual spraying (IRS), insecticide-treated mosquito nets (ITNs), long lasting insecticides treated nets (LLINs), and intermittent preventive treatment during pregnancy (IPTp). Second, prompt and effective malaria case management with antimalarial drugs mainly the artemisinin based combination therapies (ACTs). Third, strengthening health system performance through increasing capacity building and delivery of malaria interventions, sustainability and universal coverage have brought about a dramatic health impact with short and long-term benefits. Interestingly, a substantial reduction in morbidity rate as well as on average more than a 20-58% mortality rate decrease in all vulnerable groups in most of SS Africa countries compared to 97.8% in P.R. China during the last decade.
Malaria political and financial achievements from epidemic to control and elimination
Our findings showed that since the independence of the majority of African countries around the 1960's with limited capacities in malaria control and in P.R. China, political and financial commitments and strategies have permitted the achievements of essential milestones, moving malaria from epidemic towards control and elimination [1, 14, 23-27]. In the last two decades, control towards malaria elimination has been on the political agenda of several of the world’s wealthiest countries and funds have become available from the GFMAT, The US President’s Malaria Initiative (PMI), the World Bank, WHO and bilateral donors that are all financial sources for the fight against malaria. The RBM Partnership, coordinating the global fight against malaria, and major donor foundations, such as the Bill and Melinda Gates Foundation, National Institute of Health (NIH), The Coordination, Rationalization and Integration of antimalarial drug discovery and Development (CRIMALDDI), The Rockefeller Foundation, The Wellcome Trust, The ExxonMobil Foundation, USAID from the American People, The Coalition of Global Businesses have greatly increased financial support for malaria research and development as well as interventional approaches.
When analyzing on the basis of incidence and prevalence rates, the African malaria situation from 1960–2000 is comparable to that of P.R. China between 1960–1980 [4-7, 9-29]. The scaling up of malaria coverage interventions across endemic areas testified the political and financial commitment of governments and stakeholders in achieving the millennium development goals (MDGs). Most African countries that have successfully implemented health policies, witnessed an improved and sustained nationwide coverage of malaria control measures and consequently documented a substantial decline in the morbidity and mortality rates amongst the population at risk, for example South Africa, Zanzibar, Gambia, Senegal, Tanzania, Kenya, Ghana and Cameroon) [3, 22, 30-32].
Comparison of the trends of malaria morbidity and mortality rates from 1960–2011
Our findings showed that both P.R. China and Africa are located in the tropical and sub-tropics with optimal climatic and environmental conditions for the reproduction and development of Anopheles species. P. falciparum and P. vivax were shown to be major causative agents of malaria, respectively, having different degrees of virulence and similar disease pathophysiology. P. vivax accounts for 80-90% of malaria cases in the Middle East, Asia, and the Western Pacific tropical regions, 10-15% in Central and South America and less than 2% in Northern African countries [4, 16, 27, 30]. Although the overall burden of malaria is higher in Africa than in P.R. China, there is increasing evidence that the overall burden, economic impact, and severity of disease have been underestimated [4, 15-27, 30-33].
Malaria public health burden during the 1960s-1970s was characterized by an upsurge in terms of malaria incidence and mortality rate in P.R. China as a result of increasing population demography and lack of adequate health infrastructure to cater for massive remotely located rural populations. Our findings showed that malaria publications from Africa from 1980–2000 are similar to those from P.R. China between 1960-1980s, which were characterized by a high death toll amongst the risky groups including children under the age of 5 years old, pregnant women and travelers [7-9, 34-36]. Several reasons contributed to the huge toll of mortality including a higher degree of endemicity, post-independence instability in most African countries, lack of health infrastructures and resources, poor understanding of the disease and ecology, inability of “naive” leaders to generate income and/or to implement efficient healthcare reforms policy [9, 12-19, 28, 29].
The era of 1970s-1980s was marked by a significant reduction in the infectious diseases in P.R. China including a drastic fall in malaria incidence (5,000 ‰ to 500 ‰), as a result of mass patriotic and mobilization health campaigns on prevention and implementation of birth control in the early 1970s. The ravage of malaria in Africa was increasingly higher with poverty related effects on the households, community and African countries [6, 18-27, 30-37]. With the structural adjustment plan proposed to African countries and implemented with the financial support of the International Monetary Fund, and The World Bank, part of the funds were allocated into the health sector but several factors contributed to the ineffectiveness of the plans. These included lack of political commitment, inadequate management and lack of much needed infrastructure in rural areas and difficult accessibility and availability of drugs, as well as lack of qualified medical personnel, with chronic pressure mounted on a few healthcare community workers has remained a huge challenge in some countries [25-27, 30-38]. Most African countries faced the sorrowful period with alarming collision between the vicious cycle of malaria and poverty, and the impact of the Structural Adjusted Plan of the International Monetary Fund implemented in these countries. During the period 1980 – 1986, P.R. China registered an increase in morbidity rate to 500 ‰, reduction of life expectancy (less than 4 years) due to malaria, resulting from global economic crisis, dread shortage of health personnel and a weakened Chinese rural cooperative medical system. However, following by the P.R. China economic boom after 1987, there was a significant sharp drop of malaria incidence from 500 ‰ to 9.2 ‰ in 1990. This was thought to be brought about by the tremendous fundamental health system reforms, characterized by increasing support to collective welfare systems, provision of adequate preventive and curative health intervention packages through healthcare decentralization, primary healthcare reforms in 2005 and the basic healthcare with insurance schemes [17-27, 30-36]. On the basis of these analyses of the trend of events, we came to the general conclusion that translations of national policy into innovative control strategies are imperative in strengthening the healthcare systems and actions to tackle the persistent burden of infectious diseases in most endemic countries.
At the same time, the public health burden of malaria has continued to increase in most African countries due to poor coverage and accessibility to the needed population in remote areas, weaker health system and importantly the serious threat of increasing antimalarial drug and insecticide resistance, as well as an uncoordinated approach at national and regional levels since 1985 [35, 39-41]. The goals oriented interventions are urgently needed by African countries especially learning from those have successfully health policies coupled with the sustained programmes, interventions with significant reduction of the malaria burden through national wide coverage of malaria control measures and has been appraised such as South Africa, Zanzibar, Gambia, Senegal, Ethiopia, Rwanda, Tanzania and Mozambique [Please see Additional file 2[1, 2, 20-27, 30, 31]. However, the scaling up impact has not been the same in all African countries, such as The Democratic Republic of Congo (DRC) and Nigeria with a persistent burden of the disease [Figures 1a & 1b].
The Chinese government’s commitment and intensive interventions towards malaria control and elimination have been enhanced by the GFMAT, Round 1–6 and national strategic applications from 2002–2012, decentralization of Center for Disease Control and Prevention at all levels nationwide since 2000, integrated healthcare systems by broadening health financing options, improving functionality of the National Ministry of Health, improving performance, strengthening case reporting and surveillance systems in rural areas, use of IRS coupled with environmental management to reduce vectors breeding in localized hotspots such as in Tibet, Henan, Hubei, Jiangsu, Guizhou and Yunnan provinces, staff incentives and competition and working with multi-stakeholders, research institutions and private sectors. Consequently, an unprecedented fall of prevalence rate from 0.19/10,000 in 2000 to 0.035/10,000 in 2011, with increasing health system decentralization and delivery, capacity building and life expectancy of plus 30 years operating through an efficient information system network nationwide on malaria surveillance reporting coverage of 97.4% [14, 27, 35-42]. As a result of scaling up impact, the Chinese government in 2010 launched the National Action Plan for Malaria Elimination till 2020 with the National Guidelines on Malaria Surveillance and Epidemic Response in alliance with efforts in strengthening health system and capacity building in remote areas by improving investment for malaria control and elimination as well as regional collaboration on networks. Similarly, varied degrees of laudable achievements have been made in some proactive African countries committed to the scaling up of malaria control interventions resulting in a marked reduction of morbidity and mortality rates amongst the risk groups and malaria transmission being more focal, with some areas being relatively free such as South Africa, Zanzibar, Ethiopia, Equatorial Guinea, Sao-Tomé & Principe, Gambia, Senegal, Mozambique, Rwanda, Tanzania and Zambia. In contrast Angola, Cameroon, Gabon, Congo, Benin, Cote d’Ivoire and Somalia which are still having substantial risk of malaria endemicity. The DRC and Nigeria have made little progress with malaria control intervention programmes possibly due to large population size, landscape, inadequacies in health system and health policy [1, 2] [Figure 2.
Interventional approaches to malaria control towards elimination
Since 1960, malaria control strategies have achieved substantial successes and there are confounding challenges such as the inadequacies in health systems in counties, lack of access to simple and reliable early diagnosis, emergence and spread of multidrug resistant parasites, Anopheles vector resistance insecticides, factors related to environment, demographic and socio-economic status. Our findings showed that healthcare systems with efficient National Malaria Control Programmes (NMCP) having adequate national and global support on malaria control using integrated strategy, including existing early diagnosis tools and prompt treatment, combined with vector control, have shown a significant impact on reducing malaria morbidity and mortality rates.
The strategic approaches on malaria control towards elimination varied from country to country and within settings, and depended greatly on political commitment and financial potentials. These approaches have evolved: (1) modeling through estimation incidence, prevalence and to generate risk maps for all of the world's malaria endemic regions; (2) prevention through the interruption of transmission of the parasite from mosquito vector to humans (and from humans to mosquitoes) and prompt case detection; and (3) management to reduce the incidence and prevalence of malaria infections including severe cases in humans. Knowing the burden of malaria in any country is an essential component of public health planning and accurately estimating the global burden is essential to monitor progress towards the United Nations.
Modeling approaches to malaria control
Estimates based on mathematical and statistical methods are used to classify malaria risk into low to high-transmission, incidence, derive the incidence and prevalence rates, cost- effectiveness, time trends and funding-research requirements from malaria epidemiology or empirical data [42]. But each evaluation model has its strengths and weaknesses as well as to highlight areas that need to be improved to provide better assessments and accurate epidemiological data for malaria control and elimination [43, 44]. For example in 2000, it was estimated that total of 225 million malaria cases, in the 99 countries malaria endemic countries - the majority of cases (78%) were in African region, followed by the Southeast Asian (15%) and Eastern Mediterranean regions [45]. In Africa, there were 214 cases per 1,000 population, compared with 23 per 1,000 in the Eastern Mediterranean region, and 19 per 1,000 in the Southeast Asia region [46]. Sixteen countries accounted for 80% of all estimated cases globally. The estimate of malaria case incidence for the African region is 176 (110–248) million cases, 261 (241–301) million P. falciparum cases in 2007 and 214 million for year 2011 [47, 48]. Nowadays, the best assessment of malaria burden and trends must rely on a combination of surveillance and survey data. In recent years, mathematical and statistical models have been used extensively in forecasting of incidence and mortality rates, socio-economic implications in both Africa and Asia, in increasing stakeholder awareness on the disease burden and in estimating the cost (investments and cost effectiveness) in control interventions based on spatio-temporal, ecological and climatic risk factor modeling as well as in assessing the impact of interventions and challenges [49-53].
Preventive measures against malaria control
These are measures involving vector control interventions aimed at reducing transmission and thus decrease the incidence and prevalence of parasite infection and clinical malaria. Prevention with intermittent preventive treatment for pregnant women reduces the impact of placental malaria infection and maternal malaria-associated anemia. Early and effective case management of malaria will shorten its duration and prevent complications and most deaths from malaria [54]. Over the years, the preventive measures have been very effective strategies in protecting the most vulnerable groups against vector contact and progression of the infection. The two most powerful and most broadly applied interventions are LLINs [55-58] and indoor residual sprays (IRS) [59]. At the same time, behaviour change interventions including information, education, communication (IEC) campaigns and post-distribution are also strongly recommended [31, 55, 56]. These interventions act by reducing the lifespan of female mosquitoes and by reducing human-vector contact. In some specific settings and circumstances, these core interventions may be complemented by other appropriate and highly practical effective methods, such as larval source control including environmental management. However, larval control is appropriate and advisable only in a minority of settings, where mosquito breeding sites are few, fixed and easy to indentify, to map and to treat; in other circumstances, it is very difficult to find a sufficiently high proportion of the breeding sites within the fight range of the vector [60].
Malaria vector control, with LLIN, IRS or other interventions, is reported to be only effective if high coverage is achieved and requires timely sustained programme of vector control, and effective delivery operations at national, provincial and district levels [20, 22, 27, 30, 31]. In addition, practical experiences in delivery vector control interventions require capacity in monitoring vector-related and operational factors that may compromise the effectiveness of the intervention. However, the spread of insecticide resistance, especially pyrethroid resistance in Africa, is a major threat, requiring a substantial intensification of resistance monitoring within country and across borders as well as research into novel insecticides and larvicides [61, 62]. Moreover, malaria vector bionomics and vector distribution maps need to be updated periodically through vector sentinel sites in different ecological and epidemiological risk factors. For example in Kenya, the proportion of malaria outpatient visits declined from 40% in 2000 to 0% by the end of 2006, with the largest decline between 2003 and 2005. Coverage with ITNs in the area is estimated to be 65% higher than that reported on the Africa coast, and 35% of households reported use of some mosquito reduction method, such as environmental management or repellents [20, 22, 27, 30-63]. Similarly, in Rwanda, data from 20 health facilities representing every district in the country showed a decline of more than 50% between 2005 and 2007 in both inpatient and outpatient slide-confirmed malaria cases. Before 2005, the number of cases had been increasing annually, but began to decline shortly before or at the same time as mass distribution of long-lasting insecticidal bed nets and the use of ACTs during 2006–2010 [20–22].
For example, the Zambian NMCP has achieved substantial success in scaling up the use of ITNs with sulphadoxine plus pyrimethamine. ITN ownership increased substantially from 22% in 2004, to 38% in 2006, and 62% in 2008. Between 2006 and 2008, pediatric malaria parasite prevalence declined by 53% and moderate to severe anaemia by 69% [22]. In Central Africa, an urban hospital in Libreville, Gabon reported an 80% decline in the number of children with positive blood smears in the inpatient and outpatient services [22, 64, 65]. In West Africa, Gambia, where surveillance at five health facilities across the country showed a 50–85% decline in the prevalence of slide-confirmed malaria among outpatients and a 25–90% decline in malaria-related hospital admissions [23 28, 30–48]. The trend persisted over 7 years with an apparent contribution from ITN coverage, which increased three-fold to 49% over the surveillance period. Studies in Africa have shown that ITNs can reduce deaths among under-fives by up to one-third [2, 20, 27, 30, 31]. IRS for example, has been a highly effective method of malaria vector control particularly useful for achieving a rapid reduction in transmission during epidemics [54, 55]. Reports from Burkina Faso mentioned a three-fold increase in malaria cases at health facilities between 2000 and 2010 in different districts, despite increasing bed net coverage [1, 60, 65, 66]. In P.R. China, the use of LLINs in vector control interventions were integrated in the GFMAT activities in Yunnan, Hainan, and Guizhou provinces, and IRS was used in localized foci of outbreaks in some endemic provinces with a significant reduction of vectorial density to over one percent by 2010. Efforts are now devoted in combating imported malaria, resistance monitoring and containment programs in the Great Mekong region and surveillance along the Three Gorges areas of P.R. China [14-28, 30-67]. The IPTp users were documented in most countries for pregnant women living in a high transmission setting receiving at least 2 doses of an appropriate anti-malarial drug during pregnancy as well as non-immune travelers [68]. Other targeted approaches to vector control such as larviciding, environmental management, community education and mobilization are applied wherever appropriate based on scientific evidence. Recently, the applications and uses of Geographic Information Systems (GIS) and Remotes Sensing (RS) have been applied in mapping of the spatio-temporal risk factors of malaria in order to predict the impact of control interventions, possible outbreaks and monitor the vectorial density in any given areas [69-72].
Management approaches to malaria control towards elimination
Effective case management using both preventive and curative stage specific antimalarial drugs to all individuals living in malaria-endemic areas through detection of and response to malaria, epidemics through regular disease surveillance, malaria early warning systems, and adequate preparedness plans of action to ensure IRS, ITNs and antimalarial drugs are rapidly deployed when needed. Case management has been achieved over the years both through IPTp in pregnancy and infants at risk of P. falciparum infection in countries in Sub-Saharan Africa and radical treatment with stage specific monotherapy or combination antimalarial drugs. Our findings documented that since the early 1960s, the deployment of chloroquine and sulphadoxine-pyrimethamine as drugs of choice in management of uncomplicated cases and quinine in severe cases across SS Africa and P.R. China significantly helped in alleviating malaria mortality rate in Africa and P.R. China. However, the emergence and spread of chloroquine and sulphadoxine-pyrimethamine P. falciparum resistance across Africa led to The WHO recommended policy change to ACTs based on proven efficacy of chloroquine and multidrug resistance and tolerability [11, 16, 30, 73-75]. With the past trend of emergence and threat of the spread of antimalarial drug resistance in the Great Mekong region, WHO recommended that in P.R. China, both chloroquine and Dihydroartemisinin plus Piperaquine. But to also include another 3 ACTs recommended in P.R. China’s malaria control guidelines that are first line effective drugs for the treatment of uncomplicated P. vivax and P. falciparum malaria, which should be combined with a 14-day course of primaquine for the treatment of P. vivax malaria in order to prevent relapses (particularly as a component of a pre-elimination or an elimination programme), provided the risks of haemolysis in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency have been analyzed respectively [1-12, 28, 29]. Nevertheless, challenges in some African countries include inefficient health systems, poor healthcare service coverage and delivery systems, and drug shortage, counter prescriptions, self medication, fake or counterfeit drugs should be discouraged through health education, pharmaceutical regulations against the decreasing susceptibility to ACTs [76, 77]. Hence, the impact of the combined approaches and interventions in malaria control since 1960 to date is summarized below [Figure 1 and Figure 3.
Sustainability of malaria interventions through health systems strengthening
Strengthening health systems in reaching and maintaining universal coverage both require substantial efforts. Strengthening health systems is not only a malaria specific issue, rather a global development issue deserving the support of the international donor community [55]. The WHO definition of a health system sums up all organizations, institutions, people and resources whose primary purpose is to improve health. It requires adequate staff, funds, information, supplies, transport, logistics, communication, overall guidance and direction. Our findings showed that most African countries had overstretched health systems across malaria-endemic areas, with malaria accounting for an average of 25-35% of all outpatient clinic visits, and 15-35% fatal cases from all hospital admissions, the post independence till 1990s as result of political and financial constraints [45]. Efforts in improving health system strengthening have been set up in most countries in Sub-Saharan Africa and other endemic areas through the RBM and GFMAT support in achieving of MDGs targets Goal 6 and 8, mainly focusing on the most vulnerable malaria-risk population, promoting effective and sustainable malaria control through partnership with governments.
Moreover, health system strengthening in Sub Sahara Africa require the following components: (i) good leadership and governance through strong political commitment backing malaria efforts, clear definition of policy and financing frameworks, leadership and stewardship from national authorities to lead planning efforts and to coordinate all partners; (ii) sustainable financing and social protection through accessibility to adequate and timely resources for activities planned, in ways that ensure populations at risk are covered by the required delivery qualitative interventions without bearing undue personal cost; (iii) efficient and cost effective tools for malaria prevention and case management available for all populations at risk; (iv) good healthcare services delivery should be effective, safe to those that need them, when and where needed, with minimum waste of resources; (v) timely and reliable health information dissemination as well as monitoring and evaluation. Malaria control provides an important platform on which to base additional efforts to strengthen these systems [2-78]. Interestingly, the substantial decline in the last decade in Africa has been as a result of RBM, GFMAT, PMI and other donors supporting, monitoring and forecasting, service delivery by integrating the NMCP and strategies and strengthening health systems through building host country managerial and technical capacity, procurement, quality control, storage, distribution of medicines, and private sector health workers and managers [14, 79, 80]. In the case of Chinese health system support structure, the Chinese cooperative medical scheme (CMS) was first implemented in rural China in the 1950s, reaching its peak in 1978 by covering 90% of rural residents. This helped reduce Chinese mortality rate from infectious diseases during the 1960s and 1970s. With the collapse of the collective economy in the early 1980s, most villages lost their collective welfare funds, counties then began dropping the program and coverage rates fell sharply from 90% in 1980 to 5% in 1985 [18-27, 30-37]. In 2003, to further strengthen the national malaria control programmes, the Chinese government launched the national consolidated medical service (NCMS) aimed at providing health coverage for the nation’s entire rural population and the National Insurance schemes by 2010 [37]. These efforts substantially provide clues that government financial support and decentralized healthcare through Center for Disease Control and Prevention at all levels have been very important, as well as funding from the GFMAT, Round 1, 5, 6 and national strategic applications played a vital role in strengthening, building and sustaining health system efficiency and associated successes that can be derived in malaria control towards elimination. Our findings showed that there is a crucial need for capacity building to the district and local level and also outside the traditional malaria system. In addition, the National Malaria Control Program should be entrusted with the responsibilities in capacity building through training healthcare personnel, strengthening of infrastructure using the best practices in evaluating malaria laboratory diagnosis and proper clinical case management of fever and malaria, in creating a sustainable network of research activities and contribution to malaria control and integrated results of research into policy by linking health workers, researchers and policy-makers; developing and maintaining a viable pharmacovigilance system for anti-malarial drugs and strengthening malaria surveillance activities, establishment and maintenance of a sentinel site surveillance network for the provision of quality data on malaria morbidity and mortality and integrated management of malaria (IMM) through learning, policy and practice health (including malaria) interventions at all levels. In P.R. China, this task has been effectively carried out through the support of Chinese government and GFMAT, Round 1,5, 6 and national strategic applications [81], whereas such training and technical know-how are urgently needed in most endemic areas in SS Africa. Hopefully, the growing P.R. China-Africa Cooperation through the Africa-P.R. China Science and Technology Partnership program should intensify such opportunities by building capacity, supporting cross-bridge between Africa and Chinese scientists and institutions to gain from lessons learnt from P.R. China achievements and successes in moving malaria from epidemic towards malaria elimination [Figure 1a & 1b.