Impact of community-based interventions for the prevention and control of malaria on intervention coverage and health outcomes for the prevention and control of malaria

Please see Additional file 1 for translations of the abstract into the six official working languages of the United Nations.

Malaria is a parasitic infection spread by the female Anopheles mosquito and is responsible for 660,000 deaths globally and over 219 million cases of infection annually [1]. High-income countries (HICs) have been able to eliminate malaria, while many parts of low- and middle-income countries (LMICs) are still struggling to deal with malaria and vector control [1]. In 2012, out of the 104 malaria endemic countries, 79 countries are in the malaria control phase, ten are in the pre-elimination phase, ten are in the elimination phase, and five are focusing on the prevention of re-introduction [1]. A number of factors account for the existing malaria burden in developing countries including climate change, infrastructure, emerging drug and insecticide resistance, massive population and demographic shifts, and costs of containment and therapy. In Sub-Saharan Africa, the wide-scale implementation of insecticide-treated bed nets (ITNs) has been one of the main strategies to reduce malaria morbidity and mortality [2].

There are existing interventions for malaria prevention, which include indoor residual spraying (IRS), ITNs, intermittent preventive therapy (IPT), presumptive treatment, and education. Previously, malarial chemoprophylaxis with chloroquine (CQ) was generally recommended for pregnant women in malaria endemic regions, however, with the recent increase in Plasmodium falciparum resistance to CQ [3–5], the World Health Organization (WHO) recommends the use of sulfadoxine-pyrimethamine (SP) for the intermittent preventive treatment in pregnancy (IPTp). In this paper, we aim to evaluate the effectiveness of community-based interventions (CBIs) and their impact on the prevention and control of malaria.

Our review findings suggest that community-based delivery of interventions to prevent and control malaria is effective in improving ITNs ownership and usage, and reducing malaria incidence, parasitemia, malaria prevalence and anemia. However, this strategy did not have a statistically significant impact on birth outcomes, anthropometric measures, all-cause mortality, and malaria-specific mortality. These non-significant findings could be attributed to the concurrent national level malaria control measures being implemented in many of the African countries which could have led to more effective malaria control measures in both the intervention and control clusters since most of the studies included in our review are from Africa. Furthermore, the non-significant findings could also be attributable to the limited number of studies included for some of the outcomes (see Table 4). Our findings suggest a decrease in anemia prevalence, however, the mean hemoglobin remained non-significant. This could be due to various other causes of anemia coexisting with malaria in the study population (including infections, infestation, and malnutrition), the limited number of studies included, and a high level of heterogeneity in the pooled analysis. Such interactions and effect modifications should be considered when interpreting these findings.

Evidence from the subgroup analysis according to the type of interventions suggests that community-based distribution of ITNs, impregnated bed sheets, and IRS can effectively increase ITNs ownership, usage and mean hemoglobin levels, and effectively reduce parasitemia, malaria prevalence, anemia prevalence and all-cause mortality. The community-based delivery of IPT was found to be effective in reducing parasitemia and malaria-specific mortality, while community education and cleanliness campaigns alone did not show any improvement in the outcomes measured. The non-significant impact of the various types of interventions could also be attributable to the limited number of studies included for some of the outcomes in the subgroup analysis and a high level of heterogeneity. We did not find any conclusive evidence on the relative effectiveness of integrated and non-integrated delivery strategies from our quantitative synthesis due to limited data in each subgroup. However, the qualitative synthesis of the data from the included studies suggests that high coverage could be achieved at a lower cost with the integration of CBIs with existing ANC and immunization campaigns. There is a need for large-scale effectiveness trials to explore the contextual parameters associated with scaling-up CBIs for malaria prevention and management.

Merely half of the countries with ongoing malaria transmission are on track to meet the World Health Assembly’s (WHA’s) target of 75% reduction in malaria cases by 2015. The WHO recommends prompt and effective treatment with artemisinin-based combination therapies, use of ITNs by people at risk, and IRS with insecticide as the key interventions to control malaria. The past decade has witnessed some tremendous expansion in the implementation of malaria control programs with an increase in international disbursements from less than USD $100 million in 2000 to USD $1.71 billion in 2010, mainly targeting the African Region [1]. Treatment of malaria among children and pregnant women has also expanded coverage in many countries recently. However, millions of people still continue to lack access to preventive therapies, diagnostic testing, and quality-assured treatment with an emerging challenge being the resistance to artemisinins and mosquito resistance to insecticides. Some of the other reported factors affecting the delivery, access, and use of interventions to prevent malaria include unclear policy and guidance; general healthcare system issues, such as stock outs and user fees; health facility issues stemming from poor organization and leading to poor quality of care; and poor healthcare provider performance. Key determinants of coverage include education, knowledge about malaria, socioeconomic determinants, and employment status [52–55].

With the recent increase in attention geared towards community-based delivery and its ever-expanding repertoire of services, systems must be identified to ensure training, support, and incentives for CBIs. Lack of supplies including ITNs and antimalarials have also been reported as a barrier to program success, and hence routine supply of these commodities needs to be guaranteed [16]. Another major barrier to sustainability of such programs is the issue of understaffing at health units [34]. There is also a need to address the challenges of fast growing cities and enhance the health conditions of its inhabitants [17]. Scaling-up environmental activities will require resources for initial massive cleaning and structural repairs that is not possible without donor support [17]. Community involvement remains an essential component of malaria control measures as these interventions require implementation at the household level and the disease is more prevalent in settings with limited access to health facilities. Building community ownership for creating demand for ITNs and increasing trust on CHWs is pivotal for any community-based program to be successful and improve health behaviors.

Interventions such as the distribution of ITNs, net impregnation, IPTp, and IPTc have the potential to be integrated with existing programs such as ANC, immunizations, deworming campaigns and child health days, and could provide useful models for evaluation. The WHO recommends seasonal malaria chemoprophylaxis to be delivered in integration with existing community-based programs, however, a single deployment strategy has not yet been devised [1]. Community case management (CCM) that integrates the management of childhood diarrhea, pneumonia, and malaria is one of the strategies that has received government support and has the potential to improve access. This program utilizes existing CHWs to treat children during home visits and has led to an improvement in ITNs usage and timely malaria treatment for children [56–58]. Similarly, a sharp increase in the number of distributed ITNs have been observed during child health days [59, 60]. Many countries in Africa have successfully implemented various integrated models of delivery, however, these are yet to be formally evaluated for effectiveness. A recent analysis carried out in Malawi, Rwanda, Kenya, and Senegal to determine the cost of providing integrated CCM concluded that this is associated with lower costs provided it is used by sufficient numbers of patients to justify the costs of training, equipping, managing, and supervising the CHWs who provide the services [61, 62]. However, simultaneous efforts should also be concerted to prevent over diagnosis and drug resistance.

Collaborative partnerships between governments and donors for the establishment of healthier environments for malaria prevention could play a crucial role in building an ideal platform for malaria specific interventions. Such programs could be articulated in collaborative partnerships between the government and various institutions such as engineering, waste management, education, and public health. We conclude that community-based strategy to deliver malaria specific interventions including ITNs, IRS and IPT, in combination with community education and sanitation, can be effective in reducing the overall burden of malaria morbidity and mortality, especially in malaria endemic areas.